I just laid them in the sauce - when the sous vide part was done, I put them in a pan with the sauce, then went to my friends house and finished them on a hot grill. I read that putting the sauce in with them and putting it on after when finishing end up about exactly the same, except you lose sauce taking them out of the bag. This was easy and convenient, plus, after finishing the chicken, I sliced it and put it back in the pan with all the saucy goodness.
One of the guys who was there last night saw me this morning and said he's been dreaming of the chicken ever since, and he's looking to get a sous vide now.