Listen to the episode's end again, the pistol is silenced, i don't think the shooting is bad, nor do i think Pippin is truly bad, there was a theory saying he was an assassin, and i didn't think of it at first but now i get it, he is there to kill the traitor, why? Because he is no longer of use to the mallers, i think that when Burt realized "the nest" was not going respond, he ran as quickly as they could back to the tower, seeing the situation, i think it was Burt who shot. like i said the pistol was suppressed and last i checked, they only have one, unless K.C infers that when they went back to Burt's shop, he had more suppressors. Also if that is not true, i think that they had more then on suppressor, and Steven shot Pippin knowing why he was there and who sent him.