There was always talk about a plan B (namely Sting) if Hogan decided not to turn heel and form the NWO.

Now, if Hogan had refused, how much thought was given to him returning to “save” WCW (basically doing his same act that he had been doing since 1984).

Bischoff wouldn’t have been that silly as to put Hogan in that lead babyface position after he had been getting booed out of the building in the spring of ‘96, right? 
Au contraire.  The plan had always been for Hogan to return and legdrop Nash in the summer, until they radically changed direction.