Slow the video to .25x speed at 10:40 to see it in her hands, the open mouth facing towards him as she jumps up.
This doesn’t justify the shoot though! He was advancing on her with his gun drawn and screaming after she did everything he told her to do! Normal people are not trained on what to do when a butcher comes to your house and starts escalating the situation.
He wasn’t in fear for his life. He just wanted to murder someone.