I'm working on creating a template to add to articles so that we can show what universe it is in. Like for articles that are cast, authors, or part of the game, we can have a template that says something like:
"This subject has been distinguished as part of the real world and should not be taken as part of the fictional universe of the Left Behind franchise. "
And then another one for things like the Vatican:
"This subject has a counterpart in the real world. However, information in this article comes from the fictional universe of the Left Behind franchise."