I can only see shredding on the out edge/ away from the engine. The timing belt is completely seperate and encased anyway. My view is change the obvious and keep fingers crossed. I still think it might the engine might be totally screwed.Has the auxiliary (fan) belt shredded on its side nearest the engine?
If yes strands of the belt may have worked there way under the timing cover causing the timing between the crankshaft and camshaft to be disturbed.