You be the coach
It would be a wise idea to sit DD this week against the Esks. Buck will be fine and it will give him more reps in case DD goes down later in the season. Lions get a bye next week so that will give DD 2 weeks to fully recover his ankle. No point in taking chances so early in the season.
Rest him for the Edmonton game and the bye week.
Rest him. The defence can handle the Esks attack and Pierce can get the job done on offence. It will be a good learning experience for Buck.
I agree with Johnny. And if Dave pushes too hard, he'll pay for it in the end....better to be sure.