Most unfortunate, but letting a complete stranger into your house with VALUABLES was never the best idea, moreover, with a company that hasn't said anything about this kind of issue before. I suppose this system has worked, but it's beyond me how you could ever trust a stranger to live in a place that you live in regularly and store many valuables in.
I want to sympathize with the victim, but it's somewhat hard to given the circumstances. In any case, AirBnB should suck it up, fix this one situation, then go into full throttle with trying to come up with a plan to prevent future things of this sort.