Relevant: https://www.lesswrong.com/posts/Kbm6QnJv9dgWsPHQP/schelling-...
Sure it is.
The point of the fallacy is that an argument should stand on its own merit, and has nothing to do with the person making it. Guess what - experts can be wrong too (e.g. hand washing).
Appealing to an expert should not be an instant win, but an argument can be valid and useful without being sufficient to end the discussion.