It's really not a huge deal. I had Tommy John Surgery as a baseball player. The worst part for me was the fact my growth plate broke off and my tricep detached. The actual "ligament damage" really isn't painful and baseball is unique in that throwing puts a TON of stress on that joint. He doesn't have to worry about any of that as a DB.
In fact, my Doctor actually advised that I didn't get a UCL replacement because "I was done throwing a baseball competitively anyways, and it doesn't really affect your health going forward, including lifting, etc." The only reason I went through with it, is because they had to remove the growth plate and re-attach the tricep. So, it just made sense to take care of it.
This really is not a big deal at all for Sherman. I wouldn't sweat it.