Sorry about that. I was asleep and missed the whole thing. Timezones, right? Anyway, the edits were dealt with by Academyjr and MetaKnighter, and the vandal has been blocked from the wiki. Unfortunately, being content moderators, neither me nor Academyjr would have been able to block him ourselves, since that ability falls to higher ranks. I believe they filled out some form for some “Volunteer Spam Task Force” who blocked the vandal, which I didn’t even know was a thing until today.
As for making changes have to be reviewed by admins, I believe that isn’t possible, as Fandom encourages wikis to be editable by everyone so the community as a whole can maintain it. I still make sure to check each edit I see when I’m around, though, but that’s the best we can do for mass vandals.