Why hand the job off to somebody else? You've admitted that the ability of the therapists is variable.
How much time do you spend with your son? Do you explain to him the silly rituals that most people go through that he does not understand? Do you constantly reinforce that if he goes along with these silly rituals, (shaking hands, looking people in the eye when talking to them, not fiddling when engaging in conversation, not suddenly changing the subject, graceful exits, etc. etc. etc.) that life will go much more smoothly?
Maybe it makes more sense for YOU to go to some special class. Why don't YOU learn to teach these skills to your son?
He'll probably eventually figure it out himself. Personally, I think the more interaction with the "normal" world the better. He will figure it out. "I do this, they do that, I don't understand why, but they do." The more doing, the more he'll figure it out.
Putin, though, geez, just give back the ring, dude! Like my friend who will just grab your slice of pizza without asking, and doesn't understand why you would mind. OK, maybe socialization won't fix everything.