I'm not going to be much help here as we have Maggie and Daddy on Fromm. Maggie has a sensitivity to chicken and reacted badly to the chicken n vegetable flavour. All the other flavours have a slight amount of chicken in and that doesn't seem to bother her. As I'm sure you already know the Beef Frittata is grain free AND chicken free. The Fromm surf n Turf is grain free but still has small amounts of chicken in. We tried the Beef frittata purely because we wanted to switch up the protein. It was purely by accident that we discovered the two grain free flavours actually take Daddy's horrendously smelley gas away. So we're sticking with the beef and the surf n turf for the most part.
Alot of people on here have found their bullies have the same reaction to duck as they do to chicken. I'll be interested to hear how he does on the Beef.
Have you checked out Petflow?? A lot of us use them for delivery of our dog food, and that could really help your decision of what food to use because you won't be limited by whether it is available near you or not.