I personally don't think Mullen wants to be there, and hasn't for a while. There's stuff he could get away with in Starkville (not cheating, just his act), that he won't get a pass on under the bright lights at Florida. To win there though, you've still got to recruit. It's easy fishing for a coach that likes to fish for them, but he doesn't. I know he's handcuffed by the show cause stuff, but I doubt he cares about it. 1- that in itself shouldn't be too big of an impact, and 2- you're punishing a guy from doing something he doesn't care to do in the first place (be out on the road recruiting).
Where he has screwed up, IMO is that he had his eyes on the NFL ever since he got to Gainesville and found out it wasn't what he thought. With the way he's let things blow up, it would be harder for him to land a head job at that level now. Just guessing, but I think he ends up at a VT or Louisville type job and tries to recreate his success.