I have a similar kid, BeekMom, and completely understand your concerns. Our counselor advised S22 not to interview, and I understand why. All through a year of zoom, he pointed the camera at the top of his head. Hairline up. He was clearly stating his position on the matter.
However, if the motivation is there, I think coaching (scripting even) can be highly effective. Can you prep a list of questions and do a few mock interviews? This worked well for my son’s Eagle board of review. Could you zoom with a grandparent/friend/someone who might be a little uncomfortable to him just to give him the experience of being uncomfortable?
Much of this is maturational. Yes, he will eventually learn his elevator pitch etc, but for now, scaffolding basic open-ended questions will get him through.
Highly selective colleges aren’t strangers to neurodiversity 
Wishing you both all the best!