Too bad no mentally prepped CCW person was on scene.
Colonel Badger and Joe Zamudio appeaer to have done pretty well. The former Colonel reacted without hesitation, and the armed Zamudio held his fire once he saw that the shooter had been disarmed, and that opening fire could have injured those restraining the shooter or other bystanders.
Sometimes it is as important to not shoot as to shoot, particularly when dealing with those who take hostages or hide behind noncombatants.
Of course if there's a cop around, live or dead, they can be used for cover. There's a better than fair chance they're wearing a vest.