My advice...
3. Go to the range and try to figure out why he didn't put down that third dog in the initial volley.
Your first two assessments sound good, but I beg to differ with you on this third one.
First of all he had ten or more things going through his mind at the time, not to mention the adrenaline factor.
Adrenaline affects us all differently.
I've been fortunate in the outcomes in my experiences and it seems that this man came out very well, especially shooting at moving targets!
Range time won't prove a thing.
Whether that "third" dog was actually shot first, second, or last doesn't matter.
Maybe he was concentrating on the target and not sights. Not uncommon in a life-threatening situation.
Maybe the excitement /adrenaline caused trigger jerk, or not a proper hold, again not uncommon for the circumstance.
No, my hat goes off to the man for a job well done.
He and his daughter made it home unharmed.
I just hope and pray the child is not emotionally scarred for life over this.