I'll take a stab here. I don't recall if he ever bred with one of the females, but I think there is where the problem lays.
Males are notorious for going on these odd streaks of "freakishness", some every year. It seems to be linked to the males hunt for a mate. Considering that before the separation he never had to "search" for a mate
, I wonder if this could be part of it.
I know some breeders on here have noted unusually aggressive behavior from males for a few weeks following breeding. It would be interesting to see if members reported aggressive behavior when their males were roaming for mates.
Hope this helps!