The crime came to light in 2015, three years after Sheena Bora was killed.
Rahul Mukerjea, son of former media baron Peter Mukerjea, on Thursday, denied before a special court in Mumbai that he knew whether Sheena Bora was still alive.
Rahul, a witness in the 2012 Sheena Bora murder case, was being cross-examined by defence lawyers before special CBI judge S P Naik-Nimbalkar.
Sheena's mother Indrani Mukerjea is a prime accused in the murder case.
The crime came to light in 2015, three years after Sheena (24) was allegedly killed by Indrani with the help of Indrani's former husband Sanjeev Khanna, and driver Shyamvar Rai in April 2012.
To a question by Indrani's lawyer Ranjeet Sangle, Rahul said, "As per my personal knowledge, I do not know whether Sheena is alive or dead as of today.
"It is not true to say that I am fully aware of the whereabouts of Sheena and that she is alive today," he added.
The witness also denied that he was in regular touch with Sheena till the end of September 2012.
He did not conspire with Sheena to prepare a forged passport so that she could leave the country, he said in response to another question by the defence.
Rahul also denied the defence lawyer's suggestion that he "falsely implicated" Indrani Mukerjea in the case for "personal vengeance".
His cross-examination will continue on Friday.
As per the Central Bureau of Investigation, Indrani disapproved of Sheena's relationship with Rahul. She also had financial disputes with Sheena, the CBI has said.
Besides Indrani, other accused in the case include Peter Mukerjea and Sanjeev Khanna. All of them are out on bail.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)