He was killed.
No matter if it was by himself or someone else he was certainly killed.
Unless you have some evidence that he had a heart attack or stroke or died of some other natural cause?
I don’t buy suicide for this guy, he wasn’t going to spend that much time in jail and in his case jail would be some easy time country club, after which he could go back to some part of his former life. Somebody who made a living from renting out teenage girls wouldn’t suddenly have self-esteem issues.