Sorry to resurrect a week old thread, but I have this question as well. I keep seeing references to the Downloads page but see no MacOS Server beta app there; just TestFlight and Xcode. Is there some hidden downloads page with it? I'm also on Monterey waiting for an update.

No, I'm not, so that's the problem. Well that's easy to take care of. Thank you so much, that appears to be the issue.