If by "I trust her to know what's going on" you mean you would put faith in a proposition she makes based solely on her domain knowledge, that's literally the fallacy.

Sure - trust her to know the data in the space better than some random doofus. That's sensible, and why we have experts.

That doesn't mean you can grant her extra consideration when evaluating the soundness of the argument she makes with that data as support - the logic contained in that argument does NOT depend on her being a domain expert, but on being a good logician. That's what the fallacy points out.

I don't think we're disagreeing, but I wanted to clarify the distinction between her being a field expert and her being an argumentative expert.