I think it's a possibility that the blacks in that prison are affiliated with BGF and there's a partnership between them & August Marks Enterprise ( Pope's former second in command). They spared Clay on word from August until Jax disconnect the gun pipeline. Tig must die, his actions have brought additional trouble for the club. Killing that Iranian ( haven't been a Persia since centuries ago, LoL) was the nail in the coffin on himself.