I’m SO thankful for this article, by the way! I do wonder if there is any specific guidance for folks whose humidity was off and may be dealing with drowning chicks. I have looked all over the Internet but not found specific guidance for rescue in that situation. If anyone knows more, I’d love to hear it!
That's the thing, I believe I mentioned in my humidity article, starting low is better because you can (almost) always increase humidity later to slow down the air cell growth. Decreasing and going the other way is not so easy, as you have found.

So maybe if things work out for you, you can write one about what you did!
I don't know if it's been mentioned here before, but I've also seen folks try lightly sanding eggs with fine grit sand paper, to thin the shells. I don't remember if it worked or not, never tried it myself.