Update:
I purchased the property back, set it to "open resort" and it did. The staff all came out of nowhere at the back of the property (literally, just materialized), and so far, it's where it is supposed to be, they are where they are supposed to be, and I just watched roaches get stomped. The resort I sold as 1 star came back as 5 star (go figure!).
Still not gonna tempt fate, though, and build resorts in non-IP towns, and I'm not going to play world 4 as IP, either.
Oh, and the darn dog finally died, at 41 days (no gourmet food or life-extension LTR either).