Lol worked out for Idaho. And NDSU obviously has fewer connections with MWC schools than Idaho did.
CUSA in its current state is not a better place for NDSU than the MVFC/Summit. Maybe someday it will be, but there's more urgency on CUSA to get itself to proven viability than there is urgency on NDSU to accept an offer to a conference that is all but DOA at FBS. We'd be lucky to land back in the MVFC with our program intact. Very hard to recover from that, just ask Idaho. I'd rather convince the top halves of MVFC and Big Sky to move up together and just call ourselves FBS. That might be what happens anyways.
Thinking NDSU would be a strong G5 program is not the same thing as thinking NDSU should throw their lot in with just whoever. In fact, SHSU, JSU and whoever else probably joined CUSA because they aren't confident they're going to be a strong G5 program.