I read her review (and your reply to her review).
Honestly, the A/C not working is a bit of a problem, and I would see if in the future such issues can be mitigated.
If you could've caught this issue beforehand, feels like she would've stayed.
I don't think this review is too far off the mark tbh, as A/C IS a big deal on a hot summer day.
If you allowed a full refund for this incident, which I would've done for sure, then the 1* review, the listing issue, and the suspension could've been avoided. Definitely full refund for cases such as this, especially since the guest didn't stay the night!
The reason why Airbnb allows this (full refund for this case) is because, the A/C not working during a hot summer day IS a very big issue, and is grounds for a listing issue, which I'm guessing you got. I would pay very close attention to listing issues, as the next time you get an A/C related listing issue, you would be suspended for a month.