Shy, concur, but are we aware of the flight regime just prior to accident? If they were 'on a job' and hovering OGE, then your hypothesis would be bang on, but presumably if they were transiting at normal cruise speed, the effects of a TR drive failure would be offeset by the aerodynamic forces on the tail and would not necessarily result in the severe yaw/roll expected at low speed. I guess we'll have to wait and see.