I'm baffled by this, really. I don't understand why they won't do anything for you concidering the compression test came back the way that it did. I work in the parts department at a small Ford dealer, and with regard to the 6.0L Diesels being what they are, we see a lot of head gasket failures. Guys come in with popped head gaskets that are running programers, and we replace the head gaskets under warranty. Quite a few of them provide us with head studs and EGR cooler deletes, and the tech installs those parts while we have it apart. The customer takes care of the cost of the upgraded parts, and we take care of the rest. That equals a happy customer. It also keeps the truck from coming back with repeat gasket failures.
My point being that head gasket failures are a known issue with these trucks, and we do what we can for the customer. If ringland failures leading to low compression test numbers and the bad factory tune are known issues with our cars, why would SoA and the associated dealers not try to do what they can to help us?