She was certainly effective in dealing with him.
She was also very lucky.
Some of the other shooters would not have been responsive to her efforts.
Indeed.. depending on when in their bipolar phase they tried to engage in sane conversation and reason. The manic phase creates the illogic and violence. Also, think she must be a firearms owner... she used the term “round” saying “he fired a round into the ceiling”. So there is more there than a bookkeeper mayhaps.