Very interesting. Accepting that a.) Martel made the movements, b.) Martel made its own watches, c.) there was an exclusivity agreement between them and Universal for the movements, then it's not really logically inconsistent for there to be a Martel watch with a Universal-stamped movement, though it's definitely a little weird. There was clearly some intricacy in that arrangement.
This is of course assuming that watch is original and not some kind of later reconstruction. With that said I'm not sure I've seen another Martel-branded chronograph at all. Do you have other examples?