They appears to be private vehicles that were stopped or backed up by crowds. I don’t think there is anything mysterious with those 2 other vehicles involved.
The drone videos show these antifa people had obstructed the intersection and were blocking any traffic from going through.
Video from a drone showed the first of the two cars hit and knocked down protesters in the intersection. Afterwards the Challenger hit the last of the two cars stopped in the intersection. No mention of the first incident that stopped traffic.