It's an interesting request and that's why we're here: solving those problems that three minutes on Google just can't. So, dear friends, what say you? Wish the soon-to-be-wed couple all the best by adding a helpful solution to the comment feed and spread a little joy.
"Hi guys. I'm getting married in a church with a weird split-hall design. The result is that half of the attendees won't be able to see the ceremony at all! I'm wondering if I could hook up my Canon Rebel T3i up to my 3rd-generation iPad and use it as a quick-and-dirty closed-circuit display? There's no WiFi in the location, so it has to be a wired solution too. Please help me!"