I always live in fear of my car getting vandalized. I live in a town that has the highest crime rate per capita in all of Canada.
I took the "Cooper" badge off my car with dental floss... just flossed that bad boy right off. Did not damage the paint one bit. Can you not "floss" off the Mini logo? I assume it is just a super strong adhesive backing. Might be best to heat it up a bit with a blow dryer.
Nu finish worked on my VW Beetle when I used to have it. Someone keyed my car. I did about five coats of Nu Finish, and turtle wax and it was pretty much impossible to see after that. The car was silver though... red might be more difficult.
I am really sorry that happened to you. Truly.