Near the end of the film when Steven Driver is obsessively watching a film while Eric and his staff try to get him to leave, it's shown that the film is an Asian martial arts film. In reality, he was watching a film before he went on his lethal and bloody rampage, but it was the 2005 film "Kingdom of Heaven" and he kept watching a scene involving a brutal and gore-filled battle.
Steve Driver in reality was unable to try and attack Eric Joven (Eric Long in the movie) after he badly injured Chris Rachel and killed Herbert Wong. He didn't do that only because a nearby business owner named Yuri Drell used martial arts to slam Driver into a wall (suffering a wound that needed 23 stitches to close) and a stunned Driver ran out and drove away without trying to kill Eric specifically.
The plot shows both Steve and Tom being humiliated during their "big break" work for Rocket Carbone. But Steve never met Rocket and was not hired to work on the film; only Tom was. In addition, Tom wasn't fired from the production and it was completed, but legal issues prevented the final film from ever being cleared for release.
Steve told Tom and Tampa at the "family dinner" scene that he was adopted. In reality, David Hill (shown in the movie) was Steve's biological father, and Steve's mother was an African-American whom David divorced in the mid-1990s.