Here "dry hatch" means I leave my incubator running on the normal humidity in the air unless it goes below 30% and then I add a bowl of water. The last few days I bump it slightly to about 50%, then let the hatch bump it further as it goes on. But limit the high range to around 65-70. That's what works in my house.
People's climates and houses will require a different set of numbers some time.
In general it does mean that the "boost" of humidity that the normal method calls for up into the 80's and further didn't work here. It in fact drowned them.
I worked out what worked by weighing eggs for proper weight loss and air cell size and figured out the usual range for good hatching.
By doing that I also learned when they might need more humidity in the case of porous or shipped eggs that were too dry.
Good luck with the hatch...