Update: I should have gone with my instincts. The son (who lives in town) arrived with the parents from the airport and immediately started to complain that the location isn't closer to downtown Durham. My listing clearly states that the home is about 9 miles from Durham and, of course, the ABB map shows the location. He asked about my cancellation policy (which is moderate) and they decided to stay. (All this around 6:30PM).
So I took them to the basement apartment. The son immediately went to the bathroom (without asking to and then when he got out asked me if that was the bathroom the parents are supposed to use (???). If not, then it was kind of weird to just run to any bathroom in a stranger's house - but that's rather minor. And there isn't any other bathroom in the apartment). The apartment is around 900 square feet give or take - but the father asks me "is this all there is?" Most guest find the accommodations adequate and even make comments like "larger than expected" "quite spacious", etc. I'm not sure the Mom speaks much English. The son pointed out the parents are checking out Sunday morning - which is what the reservation stated - so I'm not sure why he mentioned that. The did have a lot of large luggage - more than I would need for a long weekend - but that's really minor. Still, with all else going on I'm somewhat concerned.
I left them and went about my business with the events weighing on my mind. I decided that I would waive the cancellation fee if they would leave without spending the night in order to keep my cleaning chores to a minimum. I contacted the daughter with this news. She came back stating that they really like my lovely home, the drive was no problem and they would stay. (If you happen to be a guest reading this, when a host offers you to waive the cancellation fee you should take the hint and cancel.) The son later texted me to apologize for his initial reaction.
In the midst of the interaction at the check in I neglected to get the names of the parents. No one introduced them to me. (The very first words from the son were about the location, cancelling, etc. - not an introduction of himself and his parents.) So I have contacted the daughter to give me the names and some background on the parents (like where they live). She has not responded to my request, which I have sent twice now. I will go to the apartment when I have someone who can go with me and see if I can communicate with the parents to get their names and IDs. I should have done this sooner - obviously.
I am still contemplating contacting ABB to discontinue the reservation. I think I am in my rights to do so but would appreciate any feedback. I feel like something weird is going on but don't quite know what it is.