Or work to pressure change internally, and occupy space that might have gone to a more morally flexible person if it was made vacant; but while doing so engage in supporting immoral behaviour.
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.