NCAA isn't going to laugh because every court in the country agrees that basically everything the NCAA does is illegal and violates players rights. Ncaa has taken much deserved L after L in court. A couple months ago the DOJ, for the first time, joined an anti trust class action lawsuit that challenged the transfer rule saying it is an illegal restraint on college athletes’ ability to sell their name, image and likeness and control their education. The players will win the anti trust lawsuit.
The same argument applies here. It is an illegal restraint for the NCAA to have a rule that a player who simply attempts to capitalize on his present market value by trying to become a professional is required to give up all future NIL possibilities and his college scholarship. Whether the player makes the decision or not is irrelevant, a player who does not get drafted (meaning he has no minimum guaranteed contract through the NFLs collective bargaining and has received no professional compensation ) should not prevented from returning to school.
And again, the fact the ncaa currently allows players from another revenue sport, basketball, to go through the draft and return to college (and get NIL deals) if they don't get drafted means the ncaa can't even try to claim that the rule for college football players is meant to preserve amateur status. 100% guarantee the courts would say the NCAAs rule preventing undrafted football players from returning is an illegal restraint.