IAVMMCM = It's a Very Merry Muppet Christmas Movie.
I guess it's debatable if JP Gross really died (I think it's actually said that "scooter's uncle" left them the theater). In that movie, the theater becomes a historical landmark, and can't be torn down or changed. By that logic, Tex can't tear down the theater and drill for oil (would drilling for oil with the theater intact count as a violation?). Also, going by the junior novel and what all I've read online, I guess it can be assumed that the Muppets always owned the theater, perhaps with JP's role being created for the series but not really being owner in the movie's "real world" universe.
The Muppet Wiki page seems to list various credits, for performers, songs, cast, and "uncredited cameos". I wondered if it came from the press kit, but various "edit summaries" say they're according to credits. So am I to understand that somebody kept track of all the credits (wouldn't be too surprised)?
Some interesting things about the credits, as listed at Muppet Wiki: Although Prawncracker said that Miss Poogy and Foozie are the only Moopets to talk, the credits supposedly list all Moopets except for the Janice Moopet, though they are listed as "Fozzie Moopet", "Rowlf Moopet" (the junior novel calls him Roowlf), and "Kermit Moopet". It also says that Sweetums is performed by Matt Vogel; I would have thought David Rudman would perform him, since he took over as Scooter and Janice (then again, I should be surprised Rudman didn't perform Sweetums in Letters to Santa, his first appearance since Rudman took over as some of Hunt's characters). The credits listed there also list at least one classic Muppet who reportedly (in the thread about the first preview) has no lines (though that fan could have misremembered). There's a few minor characters who I knew have dialogue who seem to be credited that I was surprised by, though just because I don't expect them to get much dialogue doesn't mean they won't get much dialogue.