I've had a similar experience just this last breeding season. What I believed to have happened was....
first, she layed the eggs too early or at least 2-3 weeks before expected. So I wasn't even ready with the incubator being set with temperature. the temperatures were fluctuating from 82-93. I lost 11 of the 19 eggs as you explained it. I don't think that the temperature was the issue because 8 of them still hatched. The 11 that collapsed did so in the first week.
is this your dragon's first clutch? because on her second clutch she laid 43 eggs and 38 hatched! so i think that it is possible that if they lay the eggs too early the survival rate is diminished as if a human has a premature birth.
jake
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