one none of my D.C. are on meds but if they were I’d want them promoted. Having said that some other young people say they feel less like themselves on the meds.
Having said that, your DD is absolutely within her rights give really clear messages about what she is comfortable with. She does not have to put up with more because he has SN. If he finds boundaries difficult then “give me space” and “Pack it in” is good advice. If he doesn’t respond well to that then asking for support from the leaders would be appropriate.
As pp said he may like her and that physical play, nudging, head on shoulder is meant to be friendly/flirty. She still doesn’t have to tolerate it though.
One of mine has been really shocked by the casual sexism and constant low level harassment in the workplace. This DD said to me when she was in school that she didn’t understand the sexism thing as she hadn’t really experienced any. She then got a job in a cafe bar and that was a really rude awakening.