Rich,
I understand what you're saying, and I cannot judge what Mike knew or didn't know. However, I think Kat specifically asked for a hypo A animal. That's what she paid for, and she didn't get it.
I too have hypos (some from you) for sale. If someone wants a hypo, I'll sell it to them. If someone calls wanting a hypo type a,b,c,d, or e specifically, I can't help that person, because I have no idea which one(s) I have. Even if I knew for a fact that a pair of mine were compatible, I have no idea which strain they have in common.
However, if someone specifically asked me for a type A hypo, and I sold them one of my Silver Queen Ghosts, it WOULD be my fault if that particular animal turned out to be hypo type D. The fact that I did not realize I wasn't providing what was paid for is not, in my opinion, anyone's fault but mine, in that situation.