Family members of a man found buried in concrete gasped in court at the “horrific and disgusting” details of an attempt to dissolve his body in chemicals.

Two defendants faced separate hearings in the Supreme Court in Brisbane on Monday over the deaths of two men in a warehouse.

Family members of the second victim, who was never found, hit out after demanding information on the whereabouts of his body after both convicted men were jailed for manslaughter.

David Lee Tan, 42, and Billy Lee Bornstein, 30, previously pleaded guilty to the manslaughter of Lachlan James Griffiths, 35, in the early hours of January 17, 2022, at the business Tan’s transport company in Coopers Plains, south of Brisbane.

Tan also pleaded guilty to being an accessory after the fact to the murder of Andrew Christopher Walsh, 35, on November 8, 2021.

Mr Walsh’s remains were found in March 2022 encased in concrete at the Coopers Plains haulage company during a police search for Griffiths’ body, which has not been located.

Judge Frances Williams said Tan provided significant assistance in a cover-up after Mr Walsh was punched and stabbed by two men who accused him of sexually assaulting a female partner.

“What was done to Mr Walsh’s body was appalling and heinous,” she said.

The remains of Andrew Christopher Walsh (right) were found in a concrete pit in south Brisbane in March 2022. The body of Lachlan James Griffiths (left) has never been located.

Griffiths’ mother Bernie is seen hugging family members outside the Queensland Supreme Court on Monday. She said her family has not received closure or justice

Judge Williams said Tan helped him place Mr Walsh’s body at the bottom of an oil seepage pit and weighed him down with a wooden pallet.

“Cleaning products and chemicals were used to try to melt the body of the deceased,” Judge Williams said, causing Walsh’s family members to gasp.

Tan later bought concrete to pour into the pit and covered it with a layer of oil and perfume in an attempt to hide the smell.

In separate sentences, Judge Williams said Tan and Bornstein did not inflict violence on Mr Griffiths but took part in a scheme to lure him from a Brisbane CBD hotel to the Coopers Plains business with the promise of a settlement payment of drugs.

Judge Williams said they both engaged in an unlawful common purpose to procure Mr Griffiths so another man, Filip Grbavac, could cause him grievous bodily harm during an “interrogation” which turned fatal in the meeting room of the warehouse.

Grbavac suspected that someone close to him had suffered serious offenses at the hands of Mr Griffiths.

“The violence must have been prolonged and extreme. You knew Mr Griffiths was being bullied and was suffering. You were aware of this and did nothing,” Judge Williams told Tan and Bornstein.

Mr Griffiths is pictured second from right with his mother Bernie and other family members. It has not been seen since it was pulled into storage in early 2022

Tan was jailed for a total of 15-and-a-half years for the manslaughter of Mr Griffiths and was an accessory after the fact to Mr Walsh’s murder.

He will be eligible for parole in September 2031, having already served 971 days in custody.

Bornstein was sentenced to nine years in prison.

He will be eligible to apply for parole in November 2028, with 721 days already served.

Griffiths’ mother Bernie has appealed for anyone with information on her son’s whereabouts to come forward so he can be buried at their local church.

“We are asking anyone who may know where he is to come forward and give us this small measure of peace,” she said outside court.

Mrs Griffiths (pictured right being comforted by a friend) has appealed for anyone with information on her son’s whereabouts to come forward so he can be buried at their local church.

Ms Griffiths said the sentencing of Bornstein and Tan was the end of legal proceedings for the family, but not the end of their grief.

“There’s no closure, no real justice,” she said.

Mr Griffiths has not been seen since his abduction, but police later obtained a photograph of his body wrapped in plastic.

Prisoners in Queensland can be refused parole if the victim’s body has not been located and the parole applicant is found to have failed to co-operate fully.

Judge Williams said any further consequences for Tan and Bornstein would be up to the parole board.

Grbavac died of severe head injuries after an alleged fight with another prisoner in February 2024.

Two men are due to stand trial in 2025 for Mr Walsh’s alleged murder.