Okay, he hasn't arisen from the depths yet, but we're getting closer. He's met most of the other cats through the baby gate with only a mild amount of hissing from them.
Most importantly, he and Dottie have completely hit it off. We've started letting the dog into the basement for short spells, which for both of them means WRESTLING MATCH! They roughhouse very vigorously, but clearly willingly. The dog's tail never stops wagging, even when the cat is biting her on the butt. The cat gets pinned pretty easily, but pops up, backs off a step, then charges right back in.
We could really give him the run of the house any time, but because I'm hosting Thanksgiving dinner next week, I think I'm going to hold off until after all that chaos subsides. We'll have enough going on with people in the house triggering Dottie's worst chihuahua impulses to guard me from the dangerous strangers who should never have been allowed in.
And no, he doesn't have a name yet. We still keep referring to him as Basement Cat or Downstairs Cat. I'm thinking of making his neuter appointment for the day after Thanksgiving, so that gives us a week to settle on something. I would be 100% on board with actually naming him Basement Cat because it would be completely on brand for me to name a pet after an Internet meme. I imagine we'll ultimately give him more of a traditional name, though.
If you haven't been following this story from the beginning, you can find the background here: Part 1, Part 2, Part 3