If the woman was in a car, and assuming she was the driver, I am hard pressed to come up with a scenario where shooting out of the window at an aggressor and hitting them in the legs is a justified use of deadly force.
Hitting the target in the legs while seated in a car implies some distance between the car and the target, which absent the target having their own firearm aimed at the car implies no imminent threat, therefore no justification.
Apparently more range time is needed.
Shooting low could most probably be a result of recoil anticipation (firearm unfamiliarity/fear), not necessarily intentional low aim, distance/bullet drop, or even intentional crippling attempt.