in your case, you said only front and rear bumper have minor scratches/dents, i assume the force of impact was small - otherwise the bumper (nowadays almost all jap's cars are hollow plastic - you didn't say what kind of car you are talking about though) which is very unlikely causing rotor warping.
you can safely deposit the check to your bank account and get a fix for the rotor. it's not a big deal. good luck.