Ad hominem is when you attack the entity making a claim using something that's not relevant to the claim itself. Pointing out that someone (general someone, not you) making a claim doesn't have the right credentials to likely know enough about the subject, or doesn't live in the area they're talking about, or is an LLM, aren't ad hominem, because those observations are relevant to the strength of their argument.

I think the fallacy you're looking for could best be described as an appeal to authority fallacy? But honestly I'm not entirely sure either. Anyways I think we covered everything... thanks for the debate :)