Just my humble opinion from my life experience. As he is young, still, may I suggest total immersion in Deaf Culture and language for five solid years? If he decides to go elsewhere after college/trade school, then whenever he can find a deaf community, he may fit in better than in the hearing world. It's time NOW to exit stage left from the hearing world. It's too late for me because I'm heavily invested in my knowledge of the hearing world and my ability to communicate with hearing people.
I sometimes wonder if I ought to have taken this route. I have very few friends out of the several hundred people I have "friended" on FB, and most of them are in the rennie world. The fact is, even though they know about my trans status and know that I'm deaf, NONE of the women are interested in me as a partner. That is the life of a person who lived as a semi-feral child for seven and a half years.
Good luck in the direction he takes. Happiness in his life depends entirely on it.