Cracked egg help!!
I've never seen an egg with that much damage make it, but I'd still give it a chance. There's going to be extra water lost through the cracks and a higher likelihood of bacteria entering.
That said, I'd just put it back in the incubator and hope for the best.
I like to keep my humidity around 35% the first 18 days, but I go by the air cell siza and adjust as needed.