Cibryll says the host can (and has) deleted entire wikis out of the blue... supposedly for zero reason, at that...
If that were to happen, then a third wiki would be a likely option... though how that would work is beyond me...
If the worst happens, either a third wiki would be made, or the first would be kept as up-to-date as the second wiki... possibly the better option? But every wiki host has its own issues...
I suppose we could repurpose the first wikia if push comes to shove. Then again, the second wiki (The Wikia) ought to counted as the main one simply because it's far more up to date.