okay I think I figured it out.
there's a runtask for removing duplicate likes (yay! another maintenance thing to slow the server down!!). Viper said something about it, but his PM was a little weird/abrupt and difficult to decipher. Basically when I started poking around the settings I was like "oooh that's what he was talking about".
so I'm guessing he ran that and that's why things disappeared the first time. Then I just now tested it out which is why things disappeared the second time.
essentially, the only real solution atm to the glitch is to either perform that runtask periodically, or shut off likes.