
Have you advised the breed Clubs and also the KC. I know the KC don't do anything but I'd still advise them. Did you have anything in writing to say that the pup would be KC registered and them sent onto you?
Join it's free, but don't name and shame them, as unfortunately you could get into trouble for doing so.
Hope it all turns out right people like this annoy me so much and unfortunately it happens in every breed.