sounds like it was just a genetic problem. I hope a necropsy will eventually shine some light on what went wrong, but if you haven't added anyone new, I wouldn't worry excessively for the rest of your collection. your skills as a keeper are redoubtable, and it's unfortunate that two females died (considering only any potential dollar loss), but I am sorry that you lost two hatchlings that you invested so much time and care in producing. hope the rest of the
clutch proves to be free from any malady.