If I were committed to feeding a home-cooked or homemade raw diet and my vet was so against it that they made me feel like I was poisoning or otherwise harming my dog, I'd be looking for another vet. I respect that vets are in a position to see the aftermath of the worst of people's dietary choices - the home-cooked diet that's just the dog getting whatever the human had for dinner themselves, even if it was outright toxic to dogs, the 'raw' diet that's just boneless, skinless chicken breasts and rice for the past three years, etc. - and that it's understandable that they might be inclined to discourage people from undertaking making their own dog diet due to this. But if a person is determined to go that route, a vet should be willing to work with them to ensure that they're providing their dog with quality nutrition and balance.
I don't, for the record, believe that kibble diets are necessarily unhealthy or equivalent to McDonalds. There's some real trash diets out there, sure, but there are also many higher-quality options, and it's unfair to vets, dogs, and owners who choose kibble diets for any number of reasons to claim otherwise. Back when I first researched raw diets there was a lot of calling kibble 'death nuggets' and talk about how people were killing their dogs with kibble, and it's really, truly, just as bad as someone telling you that you'll poison your dog by making them their own diet, no matter how much research and care you put into it.
If you can't find a vet to support you in creating a diet plan, an alternative might be using a commercial fresh food complete diet as a base, and supplementing with other whole foods. This way you know the base diet you're using is complete, balanced, and safe, but can adjust some aspects to work with your dog. There's a number of frozen raw patties or rolls, freeze-dried or dehydrated foods that are based on whole foods, and fresh food rolls. It might still be pretty expensive, depending on your country and region, but it'd be worth checking out and comparing to what you'd expect to pay for a kibble that works with your dog's allergies.