Do you have any links to the wild version?Seen all of that, and then some. The Lake Catemaco strain does not look anything like the marbled version. I've seen them in person, and many just like them online. Also, there is no doubt in my mind that the breeder in AU had a pair that carried this gene, but again, there was no provenance back to the wild, or anywhere else.
If you have provenance back to the wild, great. If not, then you have an aquarium strain of who knows what.
As with many other cichlids (I've kept many African cichlids), the ones that I have, are very likely selectively bred for certain traits. But that doesn't prove that they are a cross. It's like Eureka Red Peacocks. They were selectively bred from Swallow tails to produce a stronger red strain.
Halfmoon Bettas look nothing like the wild Betta Splendens. Are they a cross or hybrid?
Your analogy puts doubt to anyone who buys fish from a fishshop. Are you going to say someone's Neon Tetra is an "aquarium strain of who knows what" because they have no "provenanced back to the wild?"
Do you have any "provenance" that someone crossed two Veija to get a Marbled strain?