That time. It was fortunate there were more than one officer at hand as that adds (hopefully) to the hits put on the attacker. Handguns suck for defense and the more hits one can quickly get on target, the better the odds of stopping the attack. Especially when the attacker is not in their right mind.
Offhand, I can think of 5 LEOs I know that have had to fire upon someone wielding an edged weapon, one had to do it on two different occasions. One of those times was a teenager with a sword longer than the one in the video. Two of the officers were cut badly enough to end up in the hospital. One spend nearly a month and had several surgeries. Knives are not something to take lightly.
I would have shot that big crazy dude in the face. One round in the right place is all it would take, but you are right about not wanting him to reach you on the charge.