As stated Hulk Hogan was red hot before jumping back to the wwf. I think everything changes if Vince Sr. doesn't hand the keys over though. I believe Vince when he said that his dad never would have sold him his portion of the company if he knew what he was going to do the business.
Hulk Hogan would have ended up in the WWF anyways and be the top star imo. What I think would totally change things would be WM III if Hogan never came back which is the event imo that made the business really be stamped into the culture.