The clutch delay valve should remain installed if you want to keep your warranty. Removal is a popular aftermarket mod to give you a better feeling in the clutch pedal during engagement. Some argue that keeping the valve can result in premature wear since it can cause excessive slipping in the clutch under certain circumstances.
But, I think it's a moot point right now. I would encourage you to go to the dealer and take some pictures of your own. The one above isn't too clear and it's hard to see if the lining has any glazing on it. Also, the pressure plate is covered in clutch dust so it's impossible to see if it has any scorching or burn marks.
While you're there, crawl under the car and snap a pic of the flywheel.
If there's no evidence of excessive heat, burning, scorching, glazing, etc. on any of the components, then BMW will be hard pressed to find a reason to blame this failure on the driver(s) of the car. In this case, it's just a stroke of bad luck and the lining decided to disintegrate. If there's any evidence of heat build-up, then you're stuck with the bill, sorry.