Chinquapins don't require cold stratification. They will germinate immediately with the right conditions. Chestnuts require cold stratification. Cold stratification nominally takes 60 to 90 days. It is a function of the individual nut, moisture level, and temperature. If your temp drops to freezing cold stratification will slow. If moisture content of the nut drops cold stratification slows and takes longer. If the moisture content drops low enough, cold stratification stops.
So, there are a couple possibilities.
1) Did your nuts pass the float test. Some nuts will never germinate.
2) Your refrigerator could be set a bit cold.
3) The moisture content could be too low. It is good to see condensation in the bag.
At this point you have several options. If you have enough 18s to accommodate all your nuts, I'd just plant them in 18s now. They may be ready to pop. If they show no signs of mold and you plan them below the surface of the media, chances of mold are low at this point. I would soak them in water for a few hours before planting them.
Another option is to take them out and soak them luke warm water for a couple hours and then return them to the fridge and watch them each week. If you have more nuts than 18s, this will ensure the nuts are viable before they are planted.
Best of luck,
Jack