No, you don't know any such thing. I just want the truth. If your theory is true, and there is proof, I have no problem accepting it. So why didn't he shoot the lady that was there with him watching him shoot people in the parking lot ?
She wasn’t there with him. She was inside the building, and was looking at him shooting people (she was looking at him through a window. She was inside. He was outside). She saw this for a moment, and fled to a safe room further inside the building.