Trying to restore the backup database again. Looks like it might have been a mysql issue.
A little unforseen maintenance and one broken RAID controller later, we're back online. Lost a few days, though, and for some reason, the ZuckerBlog page appeared to be publishing from the MissingLinks page as well. In fact, all the blogs I manage had some kind of content bleed into other published blogs. The origin of this was that I imported the backup .sql file into the wrong version of MySQL, and although everything looked good in the Movable Type web interface, the database was moving everything around. The best way to fix this was to pull everything apart again, and reinstall the older MySQL server.
So far, everything's OK. The only thing I'm still having problems with is email posting, and I should have that fixed up in a little while.
By the way, Movable Type 5.2 looks pretty awesome. And it appears much faster than version 4, though this may actually be because I gutted the old server and replaced it with a newer one.