It should be fairly easy to get the imperfection out as long as the bumper isn't cracked. When it's warmer, sand off the dimple area of bad paint/roughness. Because it's small enough, just use a fine paint brush and brush on matching paint (also primer if needed). Sand it smooth with surrounding and do another coat. Repeat until it feels right. Brush on some clear. Make sure there's overlap with sanded cleaer near by. Then sand smooth. Do another coat and sand. Then take out the trusty buffer and you probably won't even see it after it's all said and done.
Oh yeah tell your friend that cost 500 bucks and you are nice so you won't charge him for it. But he's your bitch for a year.
graduate research associate
Center for Automotive Research
at THE Ohio State University
2004 Intrepid SXT