I wouldn't file a claim with asurion, you should be able to take it to a sprint service and repair store to have them fix it on site. Having the back cover dyed will not affect anything. You need to flash back to the stock rom and relock the phone before taking it to a store to have it repaired. Check this thread for the stock rom http://forum.ppcgeeks.com/showthread.php?t=42741 and this thread gives you the process of how to flash back http://forum.ppcgeeks.com/showthread.php?t=43266

edit: forgot about the screen being shattered lol. If it is broken to where you cannot see anything you can still relock and flash. You can flash by pc without having to see the screen on the device as well as relock. The flashing is controlled on the pc with the RUU.