it would've never worked. WCW would've been driven into the ground wether or not they had the main event stars along for the angle. Look what happened when nWo, Sting, Goldberg, Steiner all came to WWE, they got shit on. The only guys who came out of their respective returns looking good was Hogan and Flair and the only reason they did was because they were just too big of names to be dragged through the mud; the fans didn't allow it.
But yeah... back on topic, WCWs other top stars would've been treated same as Booker and Page were because Vince is petty.