Unsigned players have attended these camps. I doubt they all pay their own way. If the NIL silliness only covers camp costs it shouldn't be circumvention. Or at least circumvention above and beyond what all the other camp invites get.
The issue is that college players cannot accept money from the team, because they essential turn pro at that point.
As for the other prospects, CBA states:
15.2 (a) All Players attending Training Camps shall be paid the same per diem meal
allowances provided in Section 19(a) and shall receive lodging provided by the Club during the
period of their attendance at Training Camp.
(b) The Clubs have an option of providing breakfast and/or lunch during Training
Camp. There shall be the following deductions from the Player's per diem, each in the same
currency as the per diem is paid, for each breakfast and/or lunch provided by the Club: $12 for breakfast and $15 for lunch.
(c) All Players signed to an SPC who are not in the Entry Level System shall be
entitled to single room accommodations at Training Camp.
(d) If Training Camp is held in, or in the vicinity of, the Club's home city, a Player
who elects to live at home instead of in accommodations provided by the Club during Training Camp shall not receive any payments for lodging.