I'd say the review is petty and exaggerated, yes.
Humiliating? Only you can decide that. Personally, I would not be "humiliated" by something so slight.
It seems that she's not the first to complain about mold and mildew...and you seem to have replied the same to the other users. Like it's their fault for not reporting it sooner?
Maybe a more hands-on approach to inspection from yourself is in order.
All I would say is, make sure your properties are clean, free from mold/mildew, and don't give people anything to complain about.
But reading her reply, she complains that there were "no oven mitts" which made her sad because she was cooking Thanksgiving.
So I would suggest she is being petty and overly dramatic overall.
So take it on the chin, write it off as a loss, and make sure that mold is cleaned up.
One complaint from a random drama queen is nothing...
Two people complaining about the exact same thing? You should take note.