I wonder why they didn’t try to shoot out her tires?
Several reasons: First, tires weren't the threat, the driver was. Shooting at a moving car with a park full of people not a good idea either. DC protocol maybe? Our department has ROE where they can't fire warning or disabling shots unless absolutely necessary. Cops can't place themselves in front of a vehicle. They MUST make all attempts to get out of the way. DC is probably even more strict than our department due to the multiple agencies and the sheer number of people in close proximity.
It makes too much sense. They probably didn't cover that option in their use of weapons classes. When they were told to aim for center-mass, they figured they meant the center-mass of the vehicle, not center-mass of the tires.