I think you're missing the principles of why Bitcoin exists: obtaining security inside an anonymous but totally insecure environment. There's absolutely nothing secure with using a private key that is known to be insecure. Ethical or legal issues are outside the point here. Also, the stupidity and naivity of using an insecure key in an insecure environment, full of unreliable participants, and yelling left and right "here's the private key, my dear ethical friends which I never met but I completely blindly trust" always has a cost.

Honestly, there is no one who can even prove that puzzles 66 and 69 were solved by them, simply because the TXs that were archived by sites such as mempool.space might have actually received an already replaced TX. We'll never know.