The toplines of all of those fish look a little dodgy to me... it's hard to tell with those photos being so small, but see how there is a dip on the head, just behind the eyes (about where the gill line would be on the top of the head if it kept running round?) That shouldn't be there. Some of the photos that look like they're meant to be female (positioned next to young males) have such long ventrals that they are obviously very young (2 month) males. The photo of the father looks exactly - and I mean EXACTLY - like some of the better aquabid sellers present their stock. I would put money on that being an aquabid photo. It is easy, when you buy top quality fish off aquabid, to produce fish of an exceptional standard in F1, to enter them in shows and win. But when you don't know how to cull and how to choose which to continue the line with and which to let go, then the quality will drop off very rapidly after F1.
If the female was normal when you bought her, then it isn't the seller's fault she is deformed. BUT any good seller would do the responsible thing and would replace or refund the purchase price of such a seriously deformed fish. Trying to say that she is normal is blatantly false. Also, the fact that your other 'female' turned out to be male makes me suspect the fish are being sold too young, maybe 2.5 or 3 months. 3.5-4 months is better as it is easier for prospective buyers to judge the eventual quality of the finnage and colour, and also allows for the fish to be definitively sexed and for congenital topline, fin and scaling faults to be picked out.
Personally I wouldn't go for the melano boy, he's got a few problems as well if you want him for breeding. Firstly there is the issue with infertility in melanos, they are an extremely difficult strain to breed (and keep breeding true) so personally I'd advise against a beginner trying to breed melanos (I won't touch them, too hard.) The anal fin is set a bit far back, the caudal spread doesn't look like it's going to make 180 and the caudal branching is uneven. All of those things can be corrected but the most serious fault is the very thin caudal peduncle. You want to steer away from that in halfmoons particularly as it is unfair to breed fish whose anatomy is incapable of supporting the weight of their fully grown finnage.
I don't know the breeder and I might not be being fair to her either, but I have to say that trying to claim that fish is normal is very dodgy IMO, and would be a major red flag. There is a great deal of quality in that line BUT it's not consistent. When your line is a genetic mixup, even breeding the very best fish it produces is likely to give a great deal of (sometimes poor quality) throwbacks at least for the first two generations.