Truthfully, I'm not sure they would spending anything at all. It would be the ultimate scam by the NFL.
Get college football to sign over its rights to the NFL. From there, the NFL now has control of college football, has a new revenue stream of allegedly billions of dollars, the NFL takes whatever it wants from said revenue stream, and leaves a little behind for the universities and players.
At least private equity infuses capital into whatever business it takes over. In this case, the NFL doesn't have to spend any money. College football already generates billions. This idea is not even honorable. It's a flat out scam. A hostile takeover is more honorable than what this proposal offers.
The only thing the NFL offers in this scenario is subjugation and theft.