I feed SiĆ¢nE Burns high oats and from what I have read the reason for using it as a weight lost program is because it contains lest protein and higher fibre levels.
John Burns site
So for a start I would cut the wet food as you are just adding protein and that kind of defeats the object of using the light food. I would bump up the light food a bit to counter for the lost of the wet food.
Also the treats are a big no no as well. If you need to give her something along with your other dogs just use some of the food you have set aside for her dinner or try some veg. I have a friend with a diabetic dog who uses broccoli as treats.
I know its hard but you really do have to be cruel to be kind.
& sometimes Cassie the cocker AKA 'the black shadow''
~♥Blind Dogs See With Their Hearts♥~
My cavalier not spoilt...I'm just well trained!