I think this idea that Kane will still be the same player after being refused a move is a bit misguided. Sure, he won't down tools because he's a consummate professional, but a huge part of motivation and desire is subconscious and essentially outside of your control. So without trying to do anything different, I don't think he'll be able to keep putting in 100% effort. There's a degree of almost faking it involved.
Just imagine if you weren't allowed to leave your job. If the pay is great, you feel valued, and you feel like you owe something to your employer, you're probably going to continue trying your best anyway. But are you really going to tell me that you'd still have the raw intrinsic hunger that came naturally and inevitably when you actually wanted to be there?