The detective in charge of investigating the death of German backpacker Simone Strobel has told a coronial inquest there is no fresh evidence to justify the prosecution of her then-boyfriend.

Ms Strobel, 25, was found dead and her naked body discovered under palm fronds in a recreational facility in Lismore, northern New South Wales, in February 2005.

The kindergarten teacher had been staying at a nearby caravan park with her then-boyfriend Tobias Suckfuell, now known as Tobias Moran, his sister Katrin Suckfuell and their friend Jens Martin.

Mr Moran was arrested in 2022 to face charges of murder but they were withdrawn last year.

Yesterday, Detective Sergeant Dave Mackie confirmed his opinion that "it is probable that Simone was killed in the caravan by Tobias on the night of the 11th and 12th of February".

The court has heard this week that covert recording operations conducted on Mr Moran in 2009 and in 2020 did not uncover any incriminating evidence, and that he always denied involvement in her death.

Mr Moran's lawyer Tim Game SC told the court that at the time of Mr Moran's arrest, a report had confirmed there was no DNA evidence to link Mr Moran to Ms Strobel's death but Mr Moran had not been made aware of the test results.

Under questioning, Sergeant Mackie gave evidence that two undercover police officers were placed in a cell with Mr Moran after his arrest in the hope that he would make an admission of guilt.

"Nothing had changed in terms of evidence to justify you prosecuting him, had it?" Mr Game said.

Sergeant Mackie agreed it had not.

Sergeant Mackie denied that public comments made by Mr Moran around the time of Ms Strobel's death describing police as "kindergarten cops" had made police "very angry".

"I had no discussions with anyone in regards to being angry about that," he said.

"I didn't have any knowledge or information to suggest that."

'Unsavoury' people 

On Monday, counsel assisting the coroner Phillip Strickland SC revealed that multiple "unsavoury" people in the Lismore area had allegedly confessed to killing Ms Strobel.

The inquest heard while a police search was still underway, one man told another Lismore local "they will find what they are looking for behind the devil's stones", referring to Aboriginal stones, in the vicinity of where Ms Strobel's body was eventually located. 

The inquest was told that the man was interviewed by police in 2009 and denied ever confessing to killing Ms Strobel.

Sergeant Mackie today told the inquest the man was "an odd person" who rambled for long periods of time and seemed to believe in some kind of witchcraft, which affected the reliability of his alleged admissions.

The inquest heard Ms Strobel's body had likely been moved to the recreational centre where it was later found through a hole in the surrounding fence.

Mr Strickland asked Sergeant Mackie whether he accepted it was more likely that the person who killed Ms Strobel had local knowledge of the hole in the fence.

Sergeant Mackie said he did not accept that proposition.

"If you were searching for a location to dispose of a body, you would find a location," he said.

'Have you seen my girlfriend?'

Late in the day, the inquest began hearing evidence from Jamie Vidler, who was staying in a tent across the road from the caravan park.

Mr Vidler told the court he had not seen or spoken to Ms Strobel before her disappearance "at any point in time".

He told the court Mr Moran and Mr Martin approached his tent on the morning of February 12, after Ms Strobel went missing.

"His [Mr Moran's] exact words were, 'Have you seen my girlfriend?'" Mr Vidler said.

"I was a bit baffled to what it was all about … I wanted a description of her for a start.

"When he described her, he didn’t describe her much, but I could assure him she was not with me."

Mr Vidler will continue giving evidence when the inquest resumes tomorrow.