Mealworms can't eat their way out of a stomach. Old wives tale that won't go away.
Now you are on to something with the exoskeleton being harder to digest though.
You have mixed both together in a way that makes no sense (besides the impossible eating out theory).
Could be UV, that is a solid theory.
OP: I am sorry to hear the little dragon died in your care, it could have been from the prior poor care. They are hardy little creatures but cannot endure improper care forever, he may have been too far gone when you took over.
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