German officials on Monday ruled out suicide. They found no signs of foul play, either.
That leaves Frank Farian, the producer brains behind the Milli Vanilli lip-syncing scam, to speculate that his former charge accidentally OD'd from a toxic combo of alcohol and prescription pills.
Pilatus was found dead in a Frankfurt, Germany, hotel room Thursday. He was 33. (Early reports listed his age as 32.)
Farian told Associated Press that Pilatus showed up at his studio on Thursday "very intoxicated and shivering all over."
When Farian couldn't reach Pilatus on Friday, he alerted workers at his hotel. That's when Pilatus' body was discovered.
Pilatus recently did a stint in drug rehab, Farian says. The producer says he thinks Pilatus got his ill-fated drug prescription from that stay.
Toxilogical tests to determine the exact cause of death are pending.
Pilatus will be buried Thursday in Germany--the nation where the New York-born performer was raised by adopted parents.
With Fab Morvan, Pilatus was Milli Vanilli--the bubblegum pop duo that dominated the charts in 1988-89 with the hits, "Blame It on the Rain" and "Girl You Know It's True."
The pair won the 1989 Grammy for Best New Artist. But in late 1990, the ride was over--and the Grammy returned--when Farian revealed that Rob and Fab didn't sing a note on their records.
On Monday, Morvan said he was feeling "tremendous pain and sorrow."
"He will always be a part of me," Morvan said.