Very little detail. I'm sure they're worried about disclosing something about their stack that would open them up to more vulnerability which is understandable,

Very little detail. I'm sure they're worried about disclosing something about their stack that would open them up to more vulnerability which is understandable, but not explaining why they didn't see it in their testing... That's something they could disclose without any threats. It's easier to disclose details of a physical infrastructure outage or a bug in someone else's code/product than a bug in your own code.