99% sure you're wrong but someone else will surely chime in. Not sure how much trust I would put in someone who hatches their eggs under a heat lamp either, lol. Maintaining a proper humidity in an incubators allows the eggs to lose the correct amount of moisture so that the air cells are the proper size for the chicks to hatch. Once you reach lockdown the air sacs are already whatever size they are. You raise the humidity very high to keep the membranes moist as I mentioned earlier.
My only two experience's with Gambel quails were not good. My buddy had been hatching a bunch of bobs and pheasants for hunting season and needed more birds late in the breeding season. He brought me a couple hundred gambels and I only hatched out around 30%, the ones that didn't hatch never developed at all. The guy gave him 200 more and 5 hatched out with 290 something being infertile. We assumed because it was so late in the breeding season. That's my only experience with them....
All my other quail and pheasants have had very respectable hatch rates....