I can't say that just because it has a place for a
license plate is any suggestion that it can be treated as an "extension" of a trailer simply by moving the plate to that location. That's no different than any trailer I have ever seen and what is required to tow one behind a standard vehicle in most (if not all) states. Even a simple Tow Dolly requires a separate plate in most states.
And he isn't really saying that it allows using it in a state that doesn't allow triple towing either. If the manufacturer really believed that, they would have gathered up the necessary DMV regulations to use as a sales tool. Or at least warrant that feature for selected states where it was known to be accepted. And, what 5th wheel owner wouldn't want to know the states into which they could tow without risking a citation?
Here's a link, but don't miss the set up that has someone towing a pick-up truck behind an Idaho Tote that is attached to a Class "A" motorhome.
Idaho Tote