Sagarin has the MVC ranked higher than some divisions of lower FBS conferences. Undefeated MAC and CUSA teams get ranked all the time so I don't know how someone can say ndsu can't be. Unfortunate they can't have a late season FBS game too but there's something to be said for running through a multi game playoff compared to winning one bowl.
I'd say winning the fcs playoff is more impressive than a low level bowl against a MAC, cUSA, or sun belt team but not comperable at all to a major bowl win. I would compare NDSU to NIU last year, they legitimately were fringe top 25 but got blasted in a big time bowl. There's a line between the NIU, NDSU and Tulane seasons were they run the table against a weak slate and say that Utah team a decade ago who blew out all 13 opponents including #3 ranked Alabama in a bowl.