My goal is not to make any breeder look bad, but I do want to point out that the forty acre chesapeakes stud dog could have any status of dm. He has Deck on both sides of him who is a known carrier of dm and a lot of unknown dm status dogs. He potentially could be clear, carrier, or at risk, but given that he does have dm known in his pedigree I would be leery on which of the females you get a pup out of. There is also some clear dogs for PRA in his pedigree, but a lot of unknown statuses as well, and without knowing his true status, he should only be bred to clear bitches. His eyes and elbows haven't been checked and neither has EIC status. The only female they have tested clear for dm is their bitch "brandy" who also has hips. But she does have Distagon who was a known carrier for EIC as her grandsire. No mention of PRA. This is how I would look at it, but to each their own.
Two great places to look up information on chesapeakes is offa.org and chessieinfo.net