I had my clutch kit (DCT) replaced at 12k mile.
They told me the same thing due to "aggressive driving".
I called BMWNA and also talked to dealer's GM. I simply told them M6 is built to be driven aggressively and must be designed the way to tolerate it otherwise 328 is a perfect car
It took 2-3 months and finally they accepted to replace the clutch kit (Clutch set + Flywheel) at no cost as "Goodwill"...
Your car is under warranty and they have to replace the clutch for free.
If you want to pay, the cost of clutch + flywheel is couple thousands (without labor cost)