When the route to an Area is corrupted, sanity checks are bypassed and we step into an infinite loop that constantly attempts to find the route to that Area. I think this can happen only if you tried to delete the area and there was an error. This leaves the name of the area in the Admin Panel and on the wiki index, but all other information about it is removed.
This wouldn't cause your original issue though; perhaps you tried to delete it to resolve the original issue. Unfortunately since the original issue is gone I will have to flag that part as Cannot Reproduce. But since the wiki is accessible now since cessation of the infinite loop, I am marking this as Fixed. If you are still able to reproduce the original issue (not seeing new areas on the windex), then please reopen this issue.