What a jailbreak is worth these days.. close to a million? So training course for a few grand by someone capable of developing a jailbreak (on numerous occasions*) should be a well-spent educational investment, even if no unfixed vulnerabilities are shared (obviously, they won't be).

I'm pretty sure someone has already paid for the course and then released all the private exploits - https://twitter.com/search?q=from%3Ai0n1c%20pangu&src=typd