I took my car to a body shop to wetsand it and they removed most of the scratches, so I was pretty happy. But after washing my car today, I saw that the part that he wetsanded was a different color than the rest of the rear bumper. It was more of a hazy black. Is this supposed to happen after you sand the car? Anyone who has had this same problem or knows anything about it please help!

 

well he must have not polished it enough so you still notice scratches...Just put some 6 or 7 layers of Zaino Z-2 on that one part and it will go away.

 

imo they took some clear cote off a little too much in that one spot
something similar happened to me, took it in they replayed the clear on that spot (cant tell anything)

 

try some ScratchX on the area and see if you can remove the haze.

it's possible that the compound he used at the end was still too course.
ScratchX is like 3000grit... extremely fine polish.