"We could not locate his whereabouts," public prosecutor Sandeep Shinde told Justice A.R. Joshi, who is hearing Salman's appeal against the sessions court ruling awarding him a five-year jail term.
Shinde said Kamaal Khan was a British citizen and had earlier appeared in the magistrate's court.
As per the 'roznama', he had sought permission to go abroad which was granted, "and he vanished, when the matter was in the sessions court, we could not locate his whereabouts", Shinde said.
He said he would file his written reply in the matter within a couple of days to the high court on Salman's lawyer Amit Desai's application on Monday, seeking Kamaal Khan's examination as a witness in the case.
Later, opening his arguments in the case, Shinde said Salman was driving the car and not his driver Ashok Singh, who was brought into the picture 13 years after the accident in Bandra West which killed one pavement dweller and injured four others.
"He (Ashok Singh) comes after 13 years and deposes. No person can keep a man in employment for 13 years who has brought him a bad name," Shinde argued.
The prosecution's charge is that Salman was driving the car, his police bodyguard Ravindra Patil -- who died in 2007 due to natural causes -- was sitting to the left, while Kamaal Khan was in the back seat.
The defence has claimed that Ashok Singh was driving the car, Salman was seated to the left while Kamaal Khan was in the back seat.
The arguments will continue in the Bombay High Court on Wednesday.
The high court is currently hearing the 49-year-old Salman's appeal against the five-year sentence awarded to him on May 6 by the sessions court for the September 28, 2002 accident.