If you work outside of the organization and compel someone to act on your behalf, you will be charged with that. It's how journalists have been tripped up in the past. If someone leaks to a journo, the journo is not part of the leak. If the journo asks someone to get data to be leaked to them, they've overstepped and get into trouble. That's something to not be forgotten.

From the inside, talking to coworkers definitely seems risky. If they are not like minded, they could report you. It'd have been better to just have quit at that point.

Because of all of that, "ethical" leaking really does seem like the only option left. It's then a matter of can the leaker live with the consequences.