Complex sentence: Whether or not Barnett was in fact taking the promotion national is a matter of dispute, some wrestlers, such as Roddy Piper, say that he was in fact doing so, but prevented by fears of crossing organized crime figures involved with the sport.
Split into simpler sentences: Whether or not Barnett was in fact taking the promotion national is a matter of dispute. Some wrestlers, such as Roddy Piper, say that he was in fact doing so, but was prevented by fears of crossing organized crime figures involved with the sport.