Update:
The guy who got hit came into our office last week to thank those who gave first aid and called emergency services. He was doing okay considering. He just got a big gash on his leg and was banged up. No broken bones or other major injuries though.
We had pulled building's security camera footage and it thankfully caught the entire accident. Somebody went through the intersection Southbound after changing his mind about making a left turn. Then after he passes through the intersection decides he's going the wrong way after all. He pulled over to the side of the road then unexpectedly does a U-turn without signalling just as the motorcycle was coming up behind him. The guy clipped the front of his car and was thrown over the hood.
We provided the footage to the police. Hopefully the driver gets charged. He didn't assist the rider at all or ask if he was okay. Didn't call 911 despite the guy being obviously injured. Just a complete idiot that doesn't deserve a license.