Honestly, I don't expect him back this season. These types of injuries take a while to heal after surgery, and then he'll need to get all the strength and mobility back in his arm after having it do very little for a long time. Even if he looks like he's moving the arm well after a few months, he still may not have a lot of his original strength back—to say nothing of the kind of strength he'll need playing D-line and the stress he'll be putting that surgically repaired tendon under.
In all likelihood, the better move long-term is to let it heal and get it back as close to normal as possible for next season. But who knows—now that I've said that, I'm sure they'll find a way to prove me wrong.