@Julie668
If a booking is cancelled on check-in day, a review can be left by the guest where they are invited to
rate and comment on relevant experiences which you can personally speak to. It's clear to all here, that's the final airbnb word on the matter despite the many concerns.
Looking through your listing reviews, guests frequently mention the driving conditions, so perhaps take the colossal hint and embed a description into your blurb and even add a snapshot of the most white knuckling hairpin bend. It might even attract fresh onlooking thrill-seekers.
When replying to a review, do have a look at the copious advice here on the forum archives.
It's thought best not to get into a public bun fight with the guest to get in the final word* ( unless you are a lawyer, whereby it's mandatory), but to kind of direct your reply to a potential future booker audience.
As far as the guest entering early with the keypad, obviously that needs a rethink tweak to make it omnishambles proof.
Otherwise, maybe your guest didn't think it through. Going up a mountain top then complaining there is some stairs to get to the listing, hmm.
Good luck, your place looks superbly majestic.