Elephant in the room, yes, he really should be rolling for damage. But as Kevin's aware of Tony's AC and minimum damage, he knows that if Tony hits them, they're as good as dead anyways. And I doubt you all want to deal with twice as many/twice as large text bubbles so I can specify how much damage he's doing.
Of course, that poses the question of why he doesn't throw tougher foes at Tony, but hey. You don't always need to kill the PC's to stop them...
Indeed. Besides how we know this plays out, there's something to be said for just throwing cannon fodder at the players in a manner where you can always tweak the numbers to keep the challenge in the sweet spot. Nah, that isn't going to happen here, unless I've forgotten how this part of the film went. XD Besides things like ammunition and exhaustion, every roll is a chance at critically failing...
Author Notes:
Of course, that poses the question of why he doesn't throw tougher foes at Tony, but hey. You don't always need to kill the PC's to stop them...