I figured out what the problem was with the merging code; there were some extra tables in my document that follow a different cell arrangement and the macro didn't like them. When I deleted those tables, the code was able to run all the way through! I have been doing a lot of testing and I believe the issue with offset columns is due to either specific rows and/or the tables (corrupted?). I am still working it out to be sure.

Is there a way to present a pop-up or something where you can designate a page range for the macro to only run on?