daym, sorry to see you in that situation, should of would of could of, but ill tell you a similar situation that happend to me back in high school i used to work at country club, i was in the car and some lady backed in to me aswell, She didnt want her insurance to know so she gave me cash instead of a check of 900 bones followed her to her bank and i had cash in envelope in my hand, by the way goodluck i dont think anything of it besides you gave him a hundred dollars. Have a good one