I'm afraid I've nothing kind to say about any of the other participants involved in this debacle, (excepting Century Arms- they are in no way accountable), but I must commend Old Joe in coming forward and sharing this experience in such detail. Perhaps he'll prevent another tragedy from occurring.
BTW, Old Joe, were you shooting the rifle from the standing position? I'm trying to cipher out how your thumb was positioned just so when operating the former ex-weapon.