Well it's a trade-off. Let's hypothetically say you have an important message that could save the world or something, but scream as loud as you can, you can't make everyone hear about it. You realize the only way to reach people is to do compromise with your principles, like publishing it on a major website that doesn't align with your values; which is the lesser evil, not spreading your message, or spreading it using those corrupt channels?

I don't think there's an easy answer to this. It's easy to focus too much on not doing evil that you miss the opportunity cost of doing good.