Revelle Balmain was a 22-year-old sex worker when she disappeared during her last shift as an escort in Sydney on November 5, 1994.
She never arrived to meet her mother at the train station the following morning.
More than 31 years after Ms Balmain vanished, Coroner Joan Baptie has ruled the former model is dead.
In her findings handed down at the NSW Coroners Court on Friday, the coroner identified Ms Balmain's bosses.
The two people that ran and operated the escort agency, Jane King and Zoran Stenojevic, were involved, Coroner Baptie found.
Both have denied any involvement in Ms Balmain's disappearance.
She said Ms King and Mr Stenojevic's evidence was "littered" with inconsistencies and untruths.
''They either knew who was responsible for Ms Balmain's disappearance or were somehow involved," she said.
But there was not enough evidence to refer the couple for criminal prosecutions, the coroner said.
The pair were formerly married and have not been charged.
Coroner Baptie instead referred the matter back to NSW Police's unsolved homicide detectives, who will continue to probe what happened when Ms Balmain disappeared on the Saturday evening.
What is known is she attended a booking with client Gavin Samers in Kingsford and he dropped her at a hotel nearby about 7pm.
It was meant to be one of her last jobs as an escort before flying to Japan to work as a dancer.
Friends of Ms Balmain planned to farewell her that evening but it fell through when the aspiring dancer failed to turn up, a companion said during the inquest.
She cannot be named for legal reasons.
The two had worked together at escort agency Select Companions.
The friend said she disliked Mr Stenojevic, who she believed was infatuated with Ms Balmain.
Reports from the evening also claim a dark-coloured Holden Commodore seen in the Kingsford area of Sydney's eastern suburbs.
A loud skid and the sound of a woman's scream was heard before the car carrying multiple people sped off.
Ms Balmain's personal belongings were found strewn across several streets in Kingsford in the days following.
The items found included her diary, bank card, keys and high-heeled clogs decorated with shells.
A previous inquest in 1999 found Ms Balmain had died at the hands of a person or persons unknown and the matter was referred to the Unsolved Homicide Unit.
A fresh investigation between 2007 and 2009, followed by a formal review in 2020, all failed to produce any compelling evidence in the case.
With questions unanswered, authorities offered a $1 million reward for information on her disappearance in 2021.
13°C