His school had some classrooms with wrong to right erasure rate at over 50 standard deviations from the norm. At seven standard deviations an event happens randomly less frequently than once in 390 billion occurrences. (I'm not talking 'statistics' very clearly).
He admitted he cheated. I'm almost sympathetic with him because he's one of the teachers who admitted cheating to the original investigators.
That info wasn’t in the news story, nor did I have the links to the report you cite....on second thought throw the bum out!