Exwife behaving like a twat over DD's diet.

[PeanutButterSquash]

My youngest DD has something called GERD. It causes her to regurgitate a large amount of foods including cheese and some other dairy products, but she can eat (without issues) chicken, fish, potatoes, rice, pasta. The problem comes with being more adventerous with that.
I found some vegan cheeses for her to try,
Some weren't suitable due to having seasonings in them that dd can't eat but I found a product that she absolutely loves, tastes ok (even to me). So it's allowed me to expand her diet a bit. I've been able to adapt about 8 of her favourites just because I have this cheese she can eat.
I mentioned it to exwife and sent dd over with some cheese on her weekend (Ex has her one weekend per fortnight).
Ex has been bombarding me with links about how a vegan diet isn't suitable for children - yeah ok, but she doesn't have a vegan diet? She just can't eat most red meat, but does eat loads of fish and chicken, as well as turkey and the odd bit of ham (which is a bit 50:50 on whether she can keep it down)
I explained this to ex and ex has said I MUST stop DD eating these horrible processed products, it's not good for her, being vegan is a terrible thing etc etc.
but she's not a vegan and surely a bit of processed vegan cheese that widens her diet isn't an issue? It's violife cheese slices, not crack cocaine ffs. Plus, I know ex feeds her plenty of "processed" things (birds eye fish cakes and nuggets, anyone?) which I don't mention or have a go at her for.
Aibu to think exwife is just behaving like a twat for the sake of it and just nod and smile?

Goats cheese is a good idea, thanks. I didn't actually think of that
Glad to see I'm mostly nbu.
I'll also try to freeze violife in a sauce, I'm making lasagna later so I'll freeze a portion of the cheese sauce and see how it comes out... thanks for the suggestion.
I don't feed her blocks of cheese, it just makes some recipes that weren't previously possible without it achieveable. It's hard because a lot of things I'd normally use to flavour (garlic, onions, black pepper, bell peppers, chives, citrus, mint...) are problematic and can cause a reaction and are in almost everything (like stock cubes, gravy) Some things (basil, oregano) are fine. But it does restrict things even further and its quite difficult to make food for her that she can eat and will enjoy. When she was first diagnosed it was a nightmare but I'm slowly trying to get more creative and cook more things that she likes.