I checked out the thread that E C S Z posted on the other site. From those pictures if you look at the flaps near the tail, you can see signs of curling already. According to his post that's what the rays already look like 2-3 days before they were sold. I strongly believe the fish were sold as sick fish.
I was going to comment on his post over there but he already locked his thread... What a coward, he puts up a post to bash others, on other hand he restricts others from entering a discussion/get things clarified.
It's just sad to see hobbyists spent so much passion and hard earned money end up getting ripped off by scamming artists like this guy. I would definitely stay clear of this vendor no matter how cheap he sells, it's definitely not worth the risk and stress.
I looked at his sales complaints history, he is extremely rude when people have an issue with him, he acts like a thug/major pain in the ass. Has so many complaints as well.... selling under false advertisement, keeping people's money and having his customer pays for his problem with his fish suppliers, etc. I can't believe this sort of people exists in this hobby.
ROOK45, I wish you the very best. I am glad you bring this sort of things to light; it saved me some future stress, as I was going to order some fish from him.