He did not stop immediately, one of the protestors chased him and blocked him in until the police got there.
As for mountains of case law regarding pedestrians being hit. I dealt with that case law for 30 years. Pedestrians are sometimes found to be at fault if the are struck while on the driving surface in poorly lit areas and are wearing dark clothes, or if they suddenly walk into the line of traffic from behind an obstruction. The doctrine of last clear opportunity virtually always falls on the operator of the vehicle if there was even the most remote chance to avoid an accident, even if the driver of the vehicle had an opportunity to swerve into a fixed object rather than hit a person.
The manual of uniform traffic control doesn't mean anything if the driver broke the law to avoid the traffic control. Like say, driving up an off ramp to go around the actual on ramp that was closed.
ITs funny they say, "its thought he drove the wrong way up an off ramp." And everyone who wants to argue jumps straight to, "well, he drove the wrong way up an off ramp to get there." Do you forget how much the news makes shit up to push an agenda?