2. They can change certain rules that aren't reasonable, just because it's their project and they are handling the distribution they are free to do some bad things
As far as I know, even if the project was handled by a popular manager, they can still change the rules anytime they want by the order of the project team/developer. It doesn't have any difference because bounty managers are just being paid to follow the instructions of how the team wants to run the bounty campaign.
Sometimes it could be vice versa.
Like if the project team is like too strict or the opposite in the bounty then the bounty manager could propose a rule to them as per the forum rule.
Example if the project team isn't aware the referral links aren't allowed then a professional BM should know that that set or kind of rule isn't applicable to the forum.