My guess is they would probably find a way to trade him next summer, even if they have to retain a little money. With only one year remaining, and the cap going up, Trouba will for sure be tradeable. Why have a dead cap space penalty year added if you buy him out, not to mention you should be able to save worst case as much, if not more by trading him and only retaining a little worst case. I say he is traded next summer, not a buyout.
I do agree that it is difficult to see them being a legit SC contender this upcoming season considering they have gotten worse, not better, since the playoffs ended.