A lot of these award ceremony things are sociological/psychological and only partly merit-based. You can't just "make things up" as a staff, of course, but Coaches [some of them at least] use these things as part of their "environment forming", sending messages to the "boys" as a whole.
Also, rewarding good old soldiers is almost always a win/win situation as far as everybody feeling good. And, It wouldn't blow me away to find that Kelly judged more good coming from revving Roberson up with the award, especially if he felt Hendrix didn't need it. Everyone knows Hendrix is coming after the QB position, but maybe Cierre & Jonas don't know how hard Cam R is coming after RB.
Floyd's MVP is not only justified, but fires Big Mike up for next year as a leader. I believe that you can go right down the line and discover some multidimensionality in every choice. Rarely will we see Kelly do things without large numbers of marbles banging around in his head. Of course all of this brilliant BS goes a'gloaming if the players had a vote in it.
And, Manti for sure doesn't need the strokes. He's been getting that since Spring Practice. Diaco would pick him out of the LB+DE+NT lines and have him judge how hard the guys were hitting the sleds. Manti was the MAN from day one.