He was a consummate pro for the team and all the players spoke to it frequently, and they really didn't want to trade him. It was Jo's request.He and Cooper butted heads for sure, but I think it was more Yzerman wanting him out of the organization. Obviously speculating, but Drouin's best performances as a Bolt came at the very end, and he finally got top 6 time. He even got PP1 time when Stamkos went down, and that was a dominant PP.
Just saying, I dont feel like it ended bitterly with Drouin on the ice. Seemed more like management starting the bad attitude purge.