A little bit of both, Tactically it was a bad idea to follow him into the funnel inside the bus, she was leading with her gun drawn in one. Luckily backup was close at hand or this would ended very very differently
No bystanders were hurt.
It's a tactical mistake on the part of the idiot who got shot, thinking he can attack one officer in an enclosed area while another is right behind her. As you said, she had backup, and I don't count that as "luck" since she was aware he was there. If she didn't have that backup, maybe her decisions would have been to wait instead. (??)
She did an outstanding job of not giving up her weapon while yelling for help (from what I could see in the video).
In any physical struggle, the outcome determines whether the decisions one made were correct. Things happen so quickly, you don't have time to weigh all the facts and choices. As they say, no battle ever goes according to plan. Chaos is the norm.
I say good job! Bad guy down, and the officers and driver walked away.

Play stupid games ....
Just my opinion. There's always room for improvement, but like aircraft landings, any gunfight you walk away from with the same number of holes in your body you started with is a good one!
