feel for you, I know it is so frustrating when you think you are winning - then something upsets the apple cart. Rupert is on Tribal complete meal sausages , it is a one protein source food and can be fed to puppies - he has either Turkey or Chicken, - lamb or duck are also available, but I found these to be a bit fatty, not sure if that would help Molly.
Have put the link here for you so you can have a look if you wish
https://tribalpets.com/uk/You can get the dry food also, but Rupert prefers the sausages. (warning they are a bit expensive)
Wishing you and Molly all the best