"Damaged Driveshaft?'

JARblue

The boot sits directly above the drive shaft with room on either side and nothing really to catch on. It seems to me that the most likely scenario if the boot were to fall onto the spinning drive shaft is that it would just slip off to one side and fall on the ground. Even if the boot fell after the car had stopped, I do not believe the drive shaft would be hot enough to melt the boot to it. But if it did, there's no doubt you would hear the boot smacking the aluminum shielding around the driveshaft until it was slung off by the centrifugal force.

Plus the fact that it was a dealer$hit diagnosis it leads me to believe they are blowing smoke. OP should look at it for themselves or get a second opinion from a reputable shop as already suggested.

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