Read them separately.
9-6-1) A or K can not go out of bounds on their own accord and return, period, save for after a change of possession.
9-6-2) NO player can INTENTIONALLY go OOB and return.
9-6-1 places an added burden on A and K by preventing them from accidentally going OOB and returning, unless after change of possession. Any player can return if forced out by an opponent's block. B and R can accidentally go OOB and return.
In Scenario 1- does B42 intentionally go OOB and return? If so, its a foul. If not intentional, no foul.
In Scenario 2- Does A12 intentionally go OOB and return? If so its a violation of 9-6-2. If not intentional, then A12 can return after the change of possession as per 9-6-1. If before the change of possession but not intentional, it would violate 9-6-1.