@Von3 I can only address the review from the A/C person, since I can not tell which other review was unhappy with the shared bath.
One of the weaknesses of the "amenities" list that AirBNB gives us is that it is not possible to indicate window vs. central A/C. In houses down South, where there is central A/C, the bathrooms are actually air-conditioned. Up here in Boston, where we are far more dependent on window units and the utility costs are sky-high, they are not. I would consider this review to be an outlier. If, they hadn't mentioned that the bedroom would not cool down enough for them, I might respond to reinforce that the bathroom doesn't have A/C, but since they had two other complaints as well, I think I would let it just slide into page 2, and then 3. Your other reviews are, I suspect, far more indicative of the experience that your guests enjoy.