It is hard to say who is a fault if you don't know what coverage was called.

 

To me though, it looks like the LB is releasing the guy to the next zone and no one is covering that zone.

 

Both plays the safety bites to the right to pick up a guy that is already being covered and leaving the deep left zone completely uncovered.

 

That makes me think the safety was confused as to what zone he was supposed to cover. He acts like there are two deep safeties and leaves that side of the field uncovered.

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