Let me preface this with, I don't think he's coming back under any circumstance.
He'll play for whatever money he signs for. He won't get the $8M/year from anyone, so he'll sign for whatever he can get. For the Kings to retain his rights, it would have taken a qualifying offer of $8M/year.
Why would he come back or go somewhere else for less? Because no one has/is going to offer him $8M/year.