@Chris242, no she couldn't possibly. If they cannot show to the appointed check in, that is that and the cancellation policy would have kicked in. What an absolute pain. How Airbnb can refund without consulting host I do not understand, but have read of more than one case. I want to see the policies and procedures which are followed in the case of refunds. Has to be one, there always is.
If I were you I would go to the FB page and ask to see it, so you can more clearly understand how it was that this happened. Just ask nicely and see what happens.
Edit: Just looked at the listing and it is great. Have marked it as favourite in case I am ever in Greece (haven't been since 1986 though, about time maybe???). I have been sailing before and do not get seasick 🙂