
The best I can do with this is leave a copy of the "off map" tokens on the main map, add 100 to the initiative of the "off map" tokens (or as many hundreds needed to sort the all out, [if you are running combat on that many maps you may need counseling]), Switch maps only when the whole map will be involved, I usually provide a "camera" token, so the others can watch as it keeps them from mischief while "off map" combat is resolved.