I called the seller. I told him that I had checked the hive yesterday and there was no new brood, no eggs, etc. I told him I went back today because I didn't want to call him without being absolutely sure that there was no queen. Today I checked each of the frames of the hive to find a queen and didn't see her anywhere. I also told him there are lots of cleaned-out cells, but not a single egg or small larvae - no activity since I installed them last Friday. I also told him both of the other nuc hives I got from him at the same time are thriving - one already has a second box.
He said he would get me a queen and mail her to me. I only live 30 minutes from him, so I said if he called me, I'd come and get her.
Before I called him while I was inspecting I added to this queenless hive a frame of brood and eggs from another hive so one way or the other, they'll end up with a queen.
So all things are good.
Thanks, everyone, for the help and input.
Linda T in Atlanta