Did he ever have another time like this, even back when he was a toddler, where "control" was taken from him so completely (as adults not responding the way he had become use to, now, at this new school)?

When I was a toddler, my mother went into the hospital and I became untoilet trained :-) and my father gave me enemas, etc. but I'd wait until I was back in panties and then go, LOL. When I was in second grade, my father went to sea for 8 months, went away and I became untoilet trained again. Of course, in the 1950's no one thought/knew as much about child psychology or put two and two together in my case; my mother went away for several months and then died and here my father had gone away. . . Kicking the major supports out from under me did not make me feel secure!