FWIW, he'd be tied for 4th on the team in OBP. I too would rather just roll with Tilson and Cordell and see what we have, but he could be slight upgrade on those 2. That being said, he has no future in this org, and those two may (albeit a small chance).
Let him go on his rehab. Maybe he'll be needed due to injury when he's ready. If not, just release him. Or let him play for a couple weeks and see if someone who take the ~$2M off our hands, and then bring Tilson back.