Don't try to bend the facts while there's literal video of the confrontation, as you yourself noted. She was being commanded to step out of the vehicle (My speculation: to be arrested) and refused to do so while accelerating the vehicle quickly with an officer standing in front of her vehicle. If the drivers intent was to commit vehicular homicide or not is obviously unknown (and at this point unknowable), it was not unprovoked in any way.
Intentionally or not she was accelerating her vehicle toward someone. Regardless of if the reaction of the agent was justified, it was 100% provoked by the driver.