What about trying the canned BB Freedom? Same company, still grain-free but lower in fat and a significantly fewer amount of calories for the same amount of food.
I'd also recommend Weruva (from the Human Style line) and Tiki Dog. Both are really high quality foods that are low in calories for a larger volume. Wellness Core Reduced fat cans are a good option too as well as the Natural Balance Stews. We rotate between all of these with Toki depending what I find a deal on...she eats primarily wet food and I've found that it's easier to maintain her weight on it than kibble because she gets a larger volume of food (depending on the type I pick, obviosuly). If switching foods doesn't help trim your pup down, you can also replace a small portion of his food with frozen green beans. Increasing exercise can also go a long way...We did several short walks daily along with feeding Wellness Core RF to trim Toki down and it worked like a charm
Good luck!