2002 Volkswagen broken intake valve

I had the diesel pump replaced on my new beetle. The day after I got it back an intake valve broke off and really chewed up the first cylinder- piston, head, injector, cam shaft, con rod. Is there any connection between these two events? This is the $2800 question. They say it was a broken off chunk of the carbon deposits that did it. There is a big buildup of carbon in the manifold.

What is my next course of action?

Tim