Go with what Woody said. You are being screwed. Find another dealership that will honor warranty work and do the work properly for a nominal fee..... $7000 for a supercharger, I mean come on!!!! They will extract the money first from the warranty provider (Chrysler, if through them), then from YOU..... Run, do not walk from them.....

Also, anywhere you go for service, ask if they have a qualified SRT6 trained technician on the job. Chrysler used to make them go to class and give certifications. If they say "yes", then ask for this certification. How do you tell if the dealership is lying? It's easy, their lips are moving. Make them PROVE their statements and watch them do the work if possible.... wait around and see what they do when they work on your ride.