I'm not going to speak for state medical associations, because their discisons can be to complicated. I would never refer a patient to another doctor with that type of conviction no matter how excellent they are. I'm comfortable with the standard that you abuse children that you shouldn't be a MLB player even if you are Mike Trout good.
The guy was legally a child too. That's why it's complicated.
Professionals refer or don't refer to a specialist based on all kinds of subjective considerations, personal and otherwise. What matters on the question of "ruining a career" is the determination of the state governing body as whether the person is fit--- not whether one doctor wants to refer him. The latter is irrelevant.
As I said before, MLB has a PR element, as it should. It's a business. My own view is that MLB probably would use very similar criteria to those I posted above to determine eligibility. If he's eligible after applying all that, you are in a dream world if you think no clubs would sign a "Mike Trout good" player.
Assuming remorse, etc, think most Cubs fans would accept this guy as a TORP, Trout-like player.