North Korea recently executed what I believe is the largest known theft in history, $1.5 billion in ETH stolen from the ByBit exchange. It was easily traceable to a state-run North Korean hacking group. No police at the door, and ETH only had a temporary dip.

I'd think that if NK was sitting on a $1-10 billion Bitcoin bug, they'd execute it too before it got fixed or exploited by someone else.