Oh wow. Yes, that would be me as well. I‘m that guy in every place I work.

Maybe talk to the person and speak about an interesting video from the neurodivergent doctor or someone else who is really good at all things autism.

Like „I recently found out“ maybe about yourself or a(n imaginary) friend. So that you don’t have to hit them with „you‘re shit at socials“ but give them strong resources with a quite hefty hint. I need stuff being said pretty directly so if your colleague doesn’t take subtle hints, make it not so subtle instead. :)

Good luck! (Btw. ADHD and trauma have strong overlaps with autism so you‘d have a hard time anyway to tell them apart if you‘re not well informed already)