This is some very good advice. My eldest son is on the spectrum (also low needs now, but was moderate for a while), and he has found D&D groups to be just stimulating enough. Just as an example.
Tech can be your friend here. You can search for people with similar interests. For example, here in NL there’s an app for people who want to go on a walk (obviously, safety first of course). The point being use tech to help you discover stuff you like then find other people who are into the same thing.
And this is the real cynic in me, but the dad will be enthusiastic about going to Little Timmy’s games, and in the end, that’s probably all Little Timmy wants: some time with dad where dad’s happy to be with him.