I had a similar problem last year one baby had a deformed mouth and did not survive. The same male produced 5 clutches last year and 6 this year including the clutch with the same pairing. Zero more have been deformed.
Sometimes this just happens and I would agree to try the same pairing again to find out exactly why. Key is not to change incubation methods, change one thing at a time to find out why. Hope this helps.
Jonas