put your cat food on top of the fridge where only the cat can get to it.then work with your dog on his aggressive problems and stop feeding wet food to your dog(that's just my opinion) I herd that it does not have the nutritional value and is junk.Again not sure on that dont feed wet food.i do feed rawmeats and veggies some cooked meat and high quality kibble.
Our V was food agressive with dogs & cats when we got him at age 3 1/2 mos. The cat food, I just hid under a strong bench and bricks outside. For everone elses benefit I played with his face evertime I fed him and took his bowl away a couple of times at each feeding for probably a month. I still do it occasionally for reinforcement. This has worked well for our dog. He doesn't even care if cats & kitttens look in his bowl while hes eating.