Crook and Williamson were almost certain to be red shirted this season before picking up their injuries. Crook is brand new to the sport, and it would have been asking a bit much of him to expect him to contribute right away. It would certainly be preferable for him to learn the game while playing it in practice, but that isn't an option now. He will watch from the sidelines and get acclimated that way, which is a fine if slightly suboptimal option.
With the Bearcats talent and depth up front Williamson was headed for a red shirt in 2013 regardless, but you never want to see an injury. Shoulder injuries can be very tricky with offensive linemen because of the physical requirements of the position. UC is less than a week into the season and is already down two guys for the year. I would be lying if I said that wasn't slightly worrisome.