I hit a large plastic bumper on the freeway going about 65 yesterday. It left more black scuff marks than the op.
After asking around I decided to use acetone eventhough my clearbra installer recommended against it. The acetone did remove all the scuff marks with ease however I noticed that the areas where the acetone was applied to seemed very dull and did not shine. So I grabbed my polishing compound and began machine polishing. After about 30 mins it began to find it's shine again which made me very relieved. Although it doesn't look as good as new but I'm very satisfied with the result. I will have to see if it will begin to discolor after some time but as of now I'm a very happy camper.