As you can see, the Duramax was over a second faster and really had no issues leaving the EcoDiesel in the dust. Great video as always from the TFL guys!
I'd fight that.. call FCA and file a case ASAP! I'd counter with the question asking does FCA offer a maintenance schedule for the EGR Cooler? What could you (the customer) have done that's documented to keep this from happening.
Not much you can do at this point, as tuning is very hard to come by. Really, wait for an official fix from FCA, get emissions complaint tuning, or sell it. :(