My goodness how this thread has gone. And hence you have the problems that all people have with fish that aren't from reliable sources.
So I say you will never know for sure. For my fish that fall under that catagory I keep them in the same tank, and if they have fry I hope they get eaten.
Could they be Metriaclima estherae (O), maybe, could the be hybrids, maybe you never know. The only thing that usually gives away these guys are there mouths, so do you think they are elongated... I tend towards maybe hence maybe hybrid. But again you never know, so then the choice is yours do you want to breed and sell them as possible hybrids?
http://www.cichlid-forum.com/profiles/species.php?id=1729
It is tough, but if you are trying to get into breeding seriously don't. I mean the only way to really make it is to make a good name and if you sell fish you aren't 100% what they are then someday it will burn you.
That being said I again say they look cool, so there might be people that want possible hybrids that look cool. (Heck the ob fryeri is a great example of an hybrid that I really like.)
Anyways good luck on figuring out what is what. (And I didn't know that female peacocks could be bred to like like Taiwan Reefs, but if you never know.)