"We hope to make it, and survive," Shirzad, 34, a former interpreter for United States Special Forces, said in a video filmed as they drove through Taliban checkpoints on August 20. "It's too tough to live here. We live in fear every day."

The hot air was filled with the blaring horns of cars and motorbikes, as thousands of people crammed around the airport's perimeter. Aircraft arrived and took off in the distance as desperate Afghans tried scaling the airport walls, hoping to get on an evacuation flight.

This was Shirzad's second attempt at reaching the airport, after failing just days earlier due to the dense crowds. He knew it was dangerous to try again, especially with his wife and three young children in tow, but he believed staying in Afghanistan would have been a death sentence -- possibly for the whole family.

As the crowds pushed forward, they became caught in the pandemonium. Shirzad hurt his leg jumping over the wall. His 8-year-old son was nearly trampled. Soon after, his 2-year-old son became sick with diarrhea.

They made it out of the mayhem in one piece, but their hopes of escape were once again dashed.

They returned home, not knowing which day might be their last.

As an interpreter for US forces for five years, Shirzad had faced enemy militants on battlefields alongside US soldiers. But now, that role was a target on his back. Though the Taliban said they would not harm those who worked with foreign forces, revenge attacks have been reported; one interpreter was dragged out of his car and beheaded by Taliban militants in May, according to witnesses.

Aside from his work as an interpreter, Shirzad is also part of the persecuted Hazara ethnic minority group, and has spoken to several Western news organizations including CNN -- making him even more vulnerable.

"Why (have) the American soldiers forgotten about us? After everything we did, the sacrifices we made? Why are you leaving us behind?" he said in a tearful voice recording sent to CNN on August 18. "They're going to cut our heads off if they find my location.

"I don't want to be left behind, I don't want to be killed by the Taliban. I don't want them to kill my kids. Please, somebody, help me."

But it seemed he was on his own. The US military terminated his contract in 2013, and when he applied in 2015 for a Special Immigrant Visa (SIV) to the US, an immigration category for Afghan nationals employed by the American government, it was rejected the following year.

He said that more recently, he tried reaching out to old contacts within the military -- some didn't respond, while others wanted to help but didn't know how.

In the absence of help from official channels, a group of his friends and contacts -- former US colleagues, British special forces members, and CNN journalists -- came together in a global effort to evacuate Shirzad and his family.

After a frantic, fearful scramble, the family finally landed in Washington, DC on August 26 -- safe at last after a week-long nightmare that swung constantly between hope and despair. Shirzad documented his journey in videos, photos, and voice recordings sent to CNN.

But as terrifying as their journey was, Shirzad and his family are among the lucky ones who got out. As of late July, about 18,000 Afghans who worked for the US military had applied for a SIV in the hope of fleeing to the United States. More than 2,000 SIV applicants and at-risk Afghans have been brought to the US since the Taliban takeover -- but many more remain in limbo, feeling abandoned and betrayed as their pleas for help go unanswered.

'He undoubtedly saved lives'

Shirzad was excited to work with the Americans when he took the job as an interpreter in 2007. He quickly became a vital and beloved teammate, say his colleagues, who Shirzad refers to as his "American brothers."

He became a lead liaison between US and Afghan Special Forces, accompanying the US Navy's SEAL Team 10 on missions in the Kejran Valley in southern Uruzgan province. He helped evacuate injured Afghans, questioned detainees, and helped US soldiers navigate friend from foe on the battlefield, according to recommendation letters for his US visa application seen by CNN.

In a recommendation letter, one lieutenant commander described Shirzad's "courage and poise in harrowing circumstances," adding that "he never hid, he never shied from challenge or danger." Others called him a "valuable and necessary asset" who "undoubtedly saved the lives of Americans and Afghans alike."

One Navy SEAL described encountering a bomb during a mission. "After the explosion took place, (Shirzad) assisted me with taking charge of the Afghans to return fire while we got the injured Americans to the medical evacuation helicopter," he wrote in his recommendation letter. "It would've been impossible for me to complete that mission, let alone any of the others, if it wasn't for him."

Shirzad's contract was terminated by the US military in 2013 after he failed a routine polygraph test. Shirzad said he has no idea what he did wrong and never received an explanation. When his 2015 SIV visa application was rejected, the US Embassy cited a "lack of faithful and valuable service" in its letter.

Several Afghan translators told CNN polygraph tests were routinely used for security clearance to access US bases in Afghanistan or as part of the screening process to apply for the visa. Many, like Shirzad, were terminated after failing the polygraph tests, though were often not told why they failed.

In the US State Department's most recent report on the SIV program in April, it said applicants denied for this reason "generally have involved cases lacking the requisite positive recommendation or evaluation."

CNN reached out to the US Department of Defense, which directed questions about the use of polygraphs and visa process to the State Department. The State Department did not immediately respond to a request for comment.

The scramble to escape

After Shirzad's failed attempt to enter the airport on August 20, he knew time was running out to get his family to safety.

The US was set to end its operations in Afghanistan on August 31, after which there would be no more evacuation flights. The Taliban controlled the rest of Kabul and nearly all of Afghanistan, meaning the airport was Shirzad's only shot. And, after the chaos of his last attempt, he couldn't afford to place his children in danger again by trying to shove through the crowds.

He reached out to CNN contacts he had spoken with in July -- and soon received instructions to get ready. CNN's efforts to evacuate its own staff from Kabul had opened up a channel that could now help Shirzad.

He and his family packed up their belongings, and left before dawn on Sunday, August 22. They traveled to a rendezvous point close to the airport, where they were picked up along with nine other people looking to escape.

They were driven to the south side of the airport, then walked to the nearby Baron Hotel, which has previously housed diplomats and foreign visitors. The hotel, a heavily secure compound with a 4-meter (13.1-foot) high perimeter wall and five guard towers, has recently been expanded into a base for British soldiers and other allies to process evacuees before bringing them into the airport.

"We're good, we're inside now ... thank you so much," Shirzad said in a video filmed from the compound. "We are so close to the gate!"

It seemed like a straight shot to the airport from there: the group was picked up by US Special Forces and taken to the nearby Abbey Gate, which was manned by US Marines and had become the main entry point to the airport.

But when they arrived at the gate, the Marines refused them entry because they didn't have a visa. They were ordered to go back, despite the presence of Special Forces who had escorted them there.

After having come so far -- the closest to escape he had ever reached -- Shirzad was desperate not to turn back. He contacted CNN and a frantic day-long effort ensued, with messages and phone calls between CNN, its contacts, and security staff on the ground, spanning time zones from London to Hong Kong to Atlanta.

Seven hours later, approval was finally granted -- and Shirzad and his family were through.

"We made it ... we are really excited," said Shirzad in a video filmed from inside the airport terminal. In the video, his children hang onto his shoulders, gap-toothed grins stretching ear to ear, while his toddler babbles happily.

The family waited for nearly two days at the airport, as thousands of fellow Afghans were airlifted to safety.

During that time, several Navy SEALS and commanders who had worked with Shirzad all those years ago rallied to help, sending in letters of recommendation.

"He quite literally exemplifies what our nation looks for in those that are seeking citizenship in our great country," read one letter from a lieutenant commander. "I would fight to have him on my team again if given the chance."

Finally, it was their turn to hop on an evacuation plane, the family eventually landing in Bahrain on August 24. They spent the night in a room on a US military base, where they got to shower and enjoy some much-needed sleep in air conditioning after several days in the hot, dusty outdoors.

Early the next morning, "someone said, pack your stuff up, you've got a flight," Shirzad said in a video filmed as the family took a bus to another plane. "We still don't know where we are heading to, so hopefully it's the US."

They were brimming with excitement and high spirits during the flight. At one point, the 2-year-old fell off his seat and continued napping on the floor by Shirzad's feet; his wife began laughing, saying Shirzad had fallen off their bunk bed the previous night while sleeping as well.

Fourteen hours later, on August 26, they arrived in Washington, DC -- the start of their new life.

Families left behind

Shirzad and his family are now discovering the perks and curiosities of American life, while staying at an army base in Fort Lee, Virginia.

They find the army base's dining hall fascinating, and have discovered a love for fried chicken, ice cream, milk and protein bars. They aren't allowed off-base, so Shirzad and his sons spend their spare time playing soccer on lush grassy fields within the base.

"We are so lucky that we are saved, and we are in the United States," he told CNN on Monday. "It is beautiful to be here ... we are the luckiest people on Earth."

Shirzad is already thinking of next steps -- after their paperwork is sorted, the family might settle in Pennsylvania, California or Texas, where they have friends and family. Shirzad might become a truck driver, like many of his friends.

But hanging over everything is a deep fear for those back in Afghanistan. Shirzad worries his younger brother, only 21, might be targeted by the Taliban; his wife is also worried for her mother and brother, and wishes they could have brought her mother to the US.

But Shirzad says they now have no way out of the country. On August 26, the same day Shirzad arrived in the US, two suicide bomb attacks took place at Abbey Gate and the Baron Hotel, both sites that had facilitated evacuees.

"There's a lot of heartbreak associated with this departure," said Gen. Frank McKenzie, the commander of US Central Command, on Monday. "We did not get everybody out that we wanted to get out."

Taliban fighters entered the Kabul airport soon after the Americans left -- marking their final takeover of the last space of resistance within the capital.

The US State Department, along with dozens of governments from other countries, released a joint statement Sunday saying they had "received assurances from the Taliban that all foreign nationals and any Afghan citizen with travel authorization from our countries will be allowed to proceed in a safe and orderly manner to points of departure and travel outside the country."

But the statement included no other details on how travel in and out of the country would be organized -- and what would happen if the Taliban reneged on their promise.

On Monday, after the complete withdrawal, US leaders reiterated that they and their allies are discussing ways to reopen Kabul airport as quickly as possible. But these efforts, too, will rely on the Taliban to secure a safe passage out.

Shirzad, who is still in touch with many of his fellow interpreters in Kabul, said he has received countless messages from those fearing for their lives. They, too, deserve to be in the US after risking their own safety to help American forces, he added.

"This is the second chance for us, to continue to our life," he said. "This has all happened because we had a good team on our side. Otherwise it was impossible."