Using your race car as a weapon for retaliation like that should never be condoned and proper, stiff penalties should ensue.
The first time the yellow and white cars touched exiting the corner, I would call that a racing incident and wouldn't pin it on either one. The yellow car was loose coming out and came down the track, at the same time the white car pushes up coming off the corner and the two hit as they go for the same piece of real estate.
The second time, the yellow car does get loose and starts to come down across the front of the white car, however the driver of the white car doesn't lift at all and just drills the guy and turns him. Still a two-way deal, but I would pin that mostly on the white car, as he could have lifted and not just dumped the guy.
What the yellow car did to retaliate is something that should be considered criminal. Using a 3000lb weapon to purposefully wreck and wall someone should get you arested in an instance such as this where it was obviously done on purpose and full throttle. If you are upset with another driver, there are much better ways to handle it. Someone with a temper like that will end up killing someone and does not belong on a track.