I don't think that was all of it. Punk did an interview with Chicagowrestling.com a while back, and he said it was that Spyder Nate Webb wanted to work CZW and Ian disapproved and took the Lightheavyweight belt off Webb (went to JC Bailey) and that anyone else wanting to work CZW would be punished, but Ian then went and made a deal with CZW. Punk found that hypocritical and left Ian.
Course, when Hero returned to CZW at Redefined, Punk was with SMV to make sure nothing happened to Hero, so it's probably a combo of the two.