It matters because Facebook created their bounty program and created the rules around it. They absolutely have 100% authority to enforce them. There is nothing

It matters because Facebook created their bounty program and created the rules around it. They absolutely have 100% authority to enforce them. There is nothing supposed about either the rules or the bounty program. They are not hypothetical. They both quite obviously exist and links to them prove their existence. I don't really follow what you are arguing. The developer has the responsibility to follow the rules of the program if he wants to participate in the program. He did not. Facebook has the responsibility to enforce the rules of the program. They did. So... yes... this is all moot.