Originally based on OP's post and comments, I was confused on what was actually happening. But she's clarified the kids don't eat keto and their doctor is okay with it. She didn't originally say that when I commented.

Thus if her husband is the only one with the issue, he can cook for himself. He works from home. When I worked from home earlier this year the amount of extra time I had was ridiculous.

I don't like keto, but OP is an adult and her kids seem to get what food they want. The middle schoolers are old enough to learn to cook basic meals if they decide they want something else too. I also thought she just had 1 toddler, but I misread that and they're twins. Jesus. Husband can definitely help out with cooking if he wants different food.