@plumtheserma You have an excellent state vet lab in 4 locations in CA. They do a very thorough necropsy for $25, up to 2 a year, and they will send a prepaid overnight shipping label if you are too far from the lab.
I would recommend if you ever have a loss, to keep the body cold, but not frozen and to get a necropsy through your state vet as soon as possible. That is the only and best way to know what happened. I have no experience with Seramas, but know they can be delicate birds that may not tolerate low...