Content-Specific Roles

QUESTION 1: We are building a crowd-facing system where each registered user needs to be able to assign admins and editors for only THEIR submitted posts (not all posts on the site).

Examples

User1.editors= ed, mike, sally, pete
User1.admins= ed, sally
User1.editors= pete

We have programmers and can do custom coding. The question is, do you think such a solution is possible with AAM at all, and if so, what specific features or methods should be be examining first?

QUESTION 2: the approach above is already a compromise based on what we currently feel any plugin is likely to achieve with wordpress. But ideally, we wanted a user to allow specific users to assign specific roles for SPECIFIC posts. Back in the day, I believe this was called an ACL (accesss control list).

For example:
Post1.editors= ed, mike, sally, pete, (and/or groupX?
Post1.admins= ed, sally

If this is possible, please disregard question 1 and jump right to this one (2).

We are really desperate for a solution here. Thanks in advance.