My experiance with ABnB in a similar situation was much different. We also showed up at a home on a remote island in Panama to find that the host had misrepresented the property. We immediatly contacted ABnB who tried to work it out with the host, but he was unresponsive and they arranged to move me to another property immediatly.
The fact that we documented the issue immediatly, attempted to work with the host through the ABnB system and that the host was not responsive to ABnB made a strong case for a refund/move.
I posted a scathing review for the host (well documented) and the host eventually withdrew their listing. You should do the same
The lesson with ABnB is to do your research up front, check the location, read the reviews and do your searches before hand. This is no differant than going to a hotel, there is some buyer beware responsibility on your part. That it was not as represented that you should have been able to show with proper pictures is on the host.
Good Luck