Well, his contract was for another year, wasn't it? So, he had the choice to either stay, not play and collect the big bucks, or to leave, take a financial hit but find a club who will play him. Looks like he opted for the second.Maybe he wasn't given a choice?
We don't know the details of his pay off and probably never will but I doubt he was given the option of staying for another year.
Either way, I guess it doesn't really matter anymore.