Double check the thermometer and lower humidity the next round. The cross beak is a genetic defect. My best guess is that there is a temperature variation in the bator more so than the humidity issue by day 23. Reason be, is if the humidity was too high, I'd expect more to have pipped and drowned rather than arrest in development. With the way the yolks are starting to go in, those are closer to 19/20, with the smaller ones closer to 14-16 day range. This variatoin in development hints that there is a temperature gradient, and you may want to rotate the locations of eggs though incubation next time too.
Edited: Didn't read all the posts, but if that is a still air, you need the temp to be 101.5 at mid top of the eggs, not 99.5 (forced air), and that is probably what did them in.
Edited: Didn't read all the posts, but if that is a still air, you need the temp to be 101.5 at mid top of the eggs, not 99.5 (forced air), and that is probably what did them in.