I dismounted runflats myself off my '13 and it was a major PITA. If it were me I would make sure they will take responsibility and pay for any damage they cause. I've seen and read about way to many damaged wheels.
If they won't then take it to a place that has done GTR wheels before. Just my .02
If they won't then take it to a place that has done GTR wheels before. Just my .02