People often enquire with a few properties and then choose one when the pre-approvals come in - nothing unusual in that. As for the stats, they are really not reliable and often out of date. You might find it has updated correctly after a couple of days.
It's kind of unusual to ask people to bring their own sheets and towels - but as long as that is clear on your description then it is her mistake. She is the one who will have to cancel - or perhaps she will be happy to buy towels and sheets. If you cancel then the dates will be blocked in your diary and you may also have a financial penalty.
She will receive her money back...minus any AirBnB fee she has paid. She could contact them direct and see if they will transfer her to another place without charging another fee. They may do so...
