I can't see a scenario where he doesn't get traded.
Turner didn't sign here to be a backup at 15 mins per game. The Celtics already have a logjam at SG with Smart, Bradley and Thornton all needing minutes. James Young will need some playing time at SG/SF too. So I don't see Turner playing any SG. He's a SF and between him and Young, the position is filled.
Also, don't Green and Turner have the same agent (Faulk)? If so, I can't see Faulk steering Turner here only to get benched behind Green. So that means that Jeff Green must be going elsewhere...