I think the woman driving was speeding. Possibly also distracted driving.
Unfortunately the video only showed the cross street. But, none of the other cars in the neighborhood seem to be driving about 10 MPH. Ahhh, I see a 25 MPH sign on the cross street.
Then the councilwoman blows through at about 3x the speed of the other cars.
The cyclist clearly ran a red light, passing cars on the left to get into the intersection, and didn't even seem to look both ways.
However, if the driver was speeding, she is equally at fault, perhaps even more so.
If one knows the frame rate, angle of camera, etc... one would be able to go back and hand measure her speed determine how fast she was going when she entered the intersection, as well as how fast she was going at the time of impact. I can't see any brake lights, although it is a bad camera angle.
In the few seconds the kid was in the rear view mirror, it would have been impossible to ascertain how badly he was hurt. Apparently nothing broken, but I certainly wouldn't be happy hitting a windshield.