I have always put hatching eggs in the salad drawer - and that is now many 1000's over the years.
How long eggs will stay viable depends on the precise temperature as much as anything but when I was setting lots of eggs, I usually set them in 10's from each hen and normally got 90% or 100% fertile and 90% hatch when the oldest egg was 10-12 days old and had been in the drawer for over a week.
Lots of birds related to chickens - partridge, pheasants - lay very large clutches, perhaps as high as 20 or more, and they all hatch fine - if they didn't hatch OK there would be natural selection for hens that set smaller clutches.
Do some searching of academic or commercial sources and you can find details of how viability drops with egg age and varies with storage temperature and RH. Most will recommend that hatching eggs should never go in the refrigerator - too cold.
What's to be lost setting a non-viable egg? One less for the pan is about all.
I've kept turkey eggs in the refrigerator (top shelf) for three weeks and still had some hatch. That's longer than I would ordinarily keep them, but it was unusual circumstances. All of my hatching eggs are refrigerated and I get good hatches. I usually try to not set anything older than ten days though.