OP,
Good job for challenging him on this.
You need to focus on the language you used to describe his behaviour towards YOUR children.
"Bitterly annoyed" and "raging".
These are your words.
I have 4 children, late teens, early twenties.
No one has EVER been raging or Bitterly annoyed with them.
Who the fxxk does he think he is?
Treating YOUR children like that?
He obviously thinks he is entitled to behave towards YOUR children in that way, in THEIR home.
Completely unforgivable.
Who cares what HIS issues are.
He has inflicted his filthy rage on your boys.
Completely unforgivable.
This is NOT normal.
There is NO excuse.
Most parents would go through someone for a short cut, who dared to RAGE at THEIR children in THEIR home.
Highly abusive.
Protect your children.
You DON'T know this man, that he would think he could behave like this in your home.