Ok, I can understand about Brown, however the other players you mentioned has been playing more than enough games in that offense.
Brown being back does make a difference, I'd still find it unexpected when considering everything about both teams. For me, I'm considering "everything" we've learned about both KC and Bills this season (performance, players, injuries etc), and also the history of both these teams. So that being said, I would be somewhat surprised if now in the AFCCG Bills allow this game to be the 1st time