It could be all BS. I guess my view is that even if you can make these guys lucrative NIL offers someone who just played in a natty isn't going to make a move to sit. If we were talking Bohanon or someone who is broken then maybe they would do it, but I also think Rhule's view is at odds with most of the Huskerverse in that he doesn't want to waste reps on a guy who isn't going to be here beyond a year. They've got Haarberg and while it's ugly as fuck, he did win some games and if you're Rhule and want to be in it for the long term why would you not want to give Kaelin every opportunity to develop into a guy who can seamlessly take over for Raiola when he goes to the draft (or portal or fishing in the waters of Lake Titicaca)?
I doubt they'd need to pay this guy a huge NIL deal. I don't think anyone else will. And even if it is relatively modest by P5 standards his Nebraska NIL deal would probably a lot more than he'd get in FCS.
Rhule would be doing HH a favor - he could go back to TE
I don't think Rhule would want to throw Kaelin to the wolves if, say, Raiola got hurt in game two. You risk ruining him.
You also have the issue of not having enough real arms to properly run practices that can develop some of these young receivers, The young receivers need to be catching passes.