In Go, both users can decide not to give a review (= to “skip the review” process entirely). That code has added a way for Admins, from the Admin panel, to “unskip” a review, meaning allowing user(s) to go through the review process, if they’ve changed their mind and would like to leave a review after all.
About your second question, did you notice my reply to your similar question few days ago? Check it out.