Board Thread:Support Requests - Getting Technical/@comment-27323068-20190324221226/@comment-9605025-20190325010556

Even if you have contacted them before, that doesn't change Wikia's policies. Locking down a wiki so only admins can edit is highly frowned upon; if not a direct violation of policies. Sure, it sounds like a simple fix to make everyone an admin, but that has its own set of risks. Not to mention that every single user is going to have to ask for permission before being allowed to edit on the wiki(s).

If you have already done everything you say your have, then you don't have many options left. At this point, all you can do is keep contacting staff/VSTF about the vandal.