You know, and I know that a backdoor would have been sealed long ago, if it had even a chance of existing.
Wrong. Why is it so difficult to understand that the
main people behind Zcash (Zooko, Green) openly confirm a backdoor in Zcash without even hiding their plans?
So no, they wont seal it but open the backdoor it by themself. Also a backdoor does not need to be lot of code but simply a vulnerability. This makes Zcash worthless.