I have some insight on this topic. While on the game day committee I had a substantial commitment ($$) to make and give away free replica jerseys, kid sizes. I had 5-6 key players picked out. This was the year following the Hawk-erchiefs.(also donated funds, didn't cost the University anything). So, I had the kid jerseys all mocked up and ready to go and enough funds for hundreds of jerseys.(close to 500)
The response was I could only do the number 1 and the last 2 digits of the year. I think it was 2017, so #17 was OK. The reason was an NCAA statute that a University cannot profit off of a name or 'likeness' to a player. (apparently number 1 and 17 are not real players that year) I know it is so stupid but when challenged I was told the University staff will take the laziest approach possible. Saying "no" to football is easy and is zero risk to the University. At that time I showed UND how many other colleges had player jerseys, with players that you could make a profit off of and UNDs response was they would report it to the NCAA.
But, the story continues............since I love rules I ordered a #22 for my fast daughter(Santiago), #5 for my strongest daughter(Brady), #92 for my boy that likes to run into things(Tank), and #45 for my boy named Kolt(Cam at that time). I took all my kids to an autograph/meet the players and those players totally freaked out (in a good way), even wanting pictures on their own phones to show friends and family. The players thought it was the coolest thing, saying "I've never seen a kid wear my jersey"!! John and Brady spent 10 minutes with my girls. Players were letting my 4 year old with Tank's jersey tackle them.