Haven't used AirBnB so I don't know about the review mechanism but isn't it blind? For example, if i remember correctly, on Freelancer.com, you cant see the other party's review until you submit yours. The reviews only get posted once both parties have submitted theirs. Isn't this the same for AirBnB? If not, wouldn't implementing this resolve the issue?

Side note: You can implement a deadline for submitting review to avoid misuse where someone doesn't submit their own review in order to prevent a bad review from getting posted on their profile