Video was reversed. The decedent was actually the driver.
When cops have an “us vs them” mentality, every interaction with the public is expected to go bad...a self fulfilling prophesy.
As far as the calmness of the girlfriend, she was obviously in desperate fear of her life and trying to talk down a crazy, irrational maniac who had a gun pointed at her. If she had “freaked out”, she’d be dead, and she knew it.
Here she is today: