Also, not trying to say anything in particular about the Wagners myself here, but I used to show Arabians regionally in my teens; and in her teens, my sister went to Nationals and had a well-regarded US trainer whom we were around a lot of the time, getting the verbal lay of the land (this was the 80s and 90s).
If such a thing is indeed the case here (not saying it is yet), it would by no means be uncommon for a breeder who has been, for want of a better word, "drummed out" of one breed association; to then make a lateral move towards breeding a different kind of horse. Not at all unusual. In fact, I'm sure I've heard it said about at least two non-Wagner "Arabian" breeding and training establishments over the course of my adolescence. The theoretical establishments became such a hissing and a byword amongst the Arabian community that they had no choice except to switch gears and breeds, all the while saying bland expected stuff like "just needed a change, yeah" to their former cohort when asked.