That's funny you mention cyanide, because I said the same thing to the guy at Tropic Isle before he sold it to me. They have a full credit policy if the fish dies within 1 day and that sounded funny to me. If a fish dies in 1 day, it was either really sick to start with (which people should be able to spot), or you screwed up in acclimating. So, either way you cut it, a 1 day return policy seems like insurance on you being an idiot. Anyway, I asked him about what happens when the fish die later due to CN poisoning, he was noncommital and said that they try not to deal with people who catch with CN.
Anyways, those were my thoughts exactly!