This is FOX we're on about though, I wouldn't be amazed if they do move NASCAR for something less important and justify it with 'oh <whatever> is more important'
Hypothetical scenario, let's suppose that FOX gets the rights to the Chase instead of ESPN, would they let NCAA/NFL interfere with NASCAR or put football on a seperate channel?
FOX would never move the NFL to another channel. If FOX ever had the chase, that would almost certainly be on FS1 or FX.