>>fzeror+(OP)
If you watch the slow-mo versions of the video people have posted you can see the ICE agent in question actually fired his weapon when his arm was fully extended away from his body still in front of vehicle as he had moved his body out of the impact zone of the front of her car. That's a terrible way to discharge a weapon even if you think you life is in danger. Seems far more likely it was a panic shot out of fear he was still in front of her not realizing he was no longer in danger.
Even if she had floored it at that point, and overal she was driving pretty slowly like a panicked mom might do, his arm would have just been struck by the windshield as she passed.