I think it was definitely her fault but that's actually less relevant: as armourer it was her responsibility. And she failed at that so she is now held responsible.
Yeha I have to agree.
I appreciate this analogy is a bit silly because it would never be allowed to get to this stage.
But imagine you are going on holiday, your whole family on the plane pack full of other holiday makers children etc.
And the captain gets in the pilot seat and thinks, I dont have a bloody clue what I am doing, but **** it these things basically fly themselves right, lets puch some buttons and go, and the plane then crashes.
It was her responsility, so unless she went to her employer and made it damn clear she didnt know what she was doing, and they made her anyway, I can only think she either, carried on regardless knowing she was incompetent, or was too stupid to realse she was, and someone ended up getting killed because of it.