I agree with Joey, I think the Sixers should hang on to him until the end of the year. Even if he doesn't play well, that's a huge expirer they can give to someone eventually. If they buy him out, they still have to pay him for two more years no matter what, and they're only saving 5 mill if I remember correctly.
If they bought him out this season, and another team picked him up, could they still use his contract in a deal even though he plays somewhere else? The Sixers will still own his contract, so I'm not sure how that works.