Do you not have pku low pro food available? Here we can order pasta and pancake mixes and all sorts of food to fill those little bellies that are specifically low phe.
I don't think the formula is a meal substitute- more like a milk substitute. There are lots of low pro foods on the market . you will be amazed. The other day I made low pro apple sauce mini muffins there is less than 1mg of PHE per muffin!!! The problem is that you need to do as much fruit/veggies and you can and then suppliment with low pro foods.
If she can have unlimited fruits and veggie she will be fine for SURE (many of us on here have children with CPKU who have to measure and regulate everything- my daughter will ever be able to just eat a banana for example or most green veggies. She will live off of apples, strawberries,carrots, cucumber and a small selection of other fruits/veggies)