When something is available for other people to read, it is usually called “published”. This all thing sounds like an overly complex way to have posts which can be read by anyone (since the contributor user is basically public info) with a comment section.
I suggest you give some more thought about why do you want feedback to be private (nothing is perfect, and no matter how much feedback you get there there will always be more), but in case you truly think this is the way to go, than just publish the post as private and let people that are interested in reviewing it create a new user in a subscriber role, and leave their feedback as comments.
Having a public user with contributor credentials is a bad idea, giving him more capabilities than it has by default makes it even worse.