When asked if Kelly denies having a sexual relationship with someone under the age of consent, Greenberg replied, "Yes, he absolutely does".
The six-hour documentary Surviving R. Kelly, which aired earlier this month on United States cable channel Lifetime, includes allegations from multiple women who accuse Kelly of sexual misconduct, sometimes with minors.
An attorney for R. Kelly said Friday that the R&B star denies all allegations of sexual misconduct involving women and underage girls, including those made in a recent documentary, although he says neither he nor Kelly has watched the entire movie.
On Thursday, the singer's estranged daughter, Joann Kelly, who is also known as Buku Abi, shared a long post on her Instagram story rebuking her father and calling him a monster.
"We know what happened, and we know those things didn't happen", lawyer, Steven Greenberg, said.
Among the multiple abuse accusations, "Surviving R. Kelly" addresses the three-time Grammy winner's marriage with the late singer, Aaliyah.
R Kelly was questioned by police after they received a tip that two women were allegedly being held hostage by the singer.
Lifetime representatives did not respond to requests for comment on Greenberg's remarks.
The six-part series features women who said Kelly sexually, mentally and physically abused them.
"I haven't heard from a prosecutor's office". He asserted that in the past women have "come on to" Kelly in the hopes that he could help them in their own performing careers, then became "disgruntled" when their own careers stalled and issued false allegations.