Most CF repair places do not even do forks but you could contact one of the best Carbon Repair – Calfee Design to see what they have to say about it. At least two places I've checked mention they don't do forks due to the cost is usually more than a new fork but not necessarily safety concerns. My thought is that if this shredded so easily how much strength was that layer supplying in the first place and would a repair really not be strong enough? Not going to recommend what the OP should do but is a repair really out of the question with snapped-in-two frames being safely repaired?