The generic and ambiguous description of the device may have been chosen specifically in the hope that one might think that. If it really was an RTG, there does

The generic and ambiguous description of the device may have been chosen specifically in the hope that one might think that. If it really was an RTG, there does not seem to be anything to gain by not saying so. Furthermore, an RTG does not seem to be a likely cause of an explosion, though I suppose you could seal one up in a fluid-filled vessel without effective cooling and without a safety valve.