Well I was feeling lucky, until I found this.. broken cam plate
Was there a "spacer" or washer between the cam gear and the cam? That cam has a built-in spacer.
I think what you are seeing there IS the spacer, still hanging on the cam, which with a modern timing set would allow the cam to bang around and break the plate when it bound up.
Cams don't get the integral spacer on an FE, the timing sets do, at least now it looks like a logical reason why it ate itself
See if that little washer comes off the end, that's be the smoking gun, then pull the cam, it's likely junk, and then see if you can get a good look at the cam bearings. If the cam bearings and block around them didn;t get beat, slap it together with a fresh cam (and plate!) and go.