This issue with duplicated wikias is all over us, everywhere. While the information in this wiki, Clamp wiki, is not supposed to be large enough as there should be other wikis with better information. Though, as you've said there are 2 chobit wikis and none of them have active admins or enough info on them.
We can't really do anything to erase either of them. I wish someone would take over one of the wikis as an admin and expand the articles.