Injuries happen at RB a lot and I really hope that one of the Grad Transfers are there and ready to make a splash if Katoa goes down. I think we saw last year with Hadley that good things can happen with a backup who is ready when his number is called.
Ideally, Katoa is stronger and more durable this year and able to put up a 1000 yard season, but, as a fan, I would be happy to see Williams or Eskupa put up those yards too. Either one of them could find this chance at BYU as their window to prove they can play in the NFL. That kind of motivation could yield solid results if the OLine keeps improving.