Airbnb Support told me the same thing. That one bad review though was from a person who booked for someone else - her brother who had a mental illness and was threatening - and Airbnb told the woman she violated the rules and he had to leave immediately.
She was allowed to write a review (1 star) with the complaint she didn't get her money back. I'd push it but knowing it disappears from the rankings at the end of this month, makes it seem not worth the effort. 🙂
Thanks so much for responding.