I still do not comprehend how a tag axle on a TC can function... especially going over dips or bumps in the road.
IIRC, I think a member mentioned that the tag wheels steer which makes sense, but I do not know how it can articulate, especially like the one in the OP's image.
On second look, it seems to be a poor photo chop image... tree branches do not line up, neither does the horizontal cut line of the TC itself. Color of the siding is not consistent. The camper behind the old car has a gap that does not line up to make seem as if part of that background camper is missing.