The only feed I could find had 28% protein, so I added one part chopped/ground rolled oats (not instant) to four parts feed to get the protein down to about 20%, sprinkled a teaspoon of chick grit on each 6 inch diameter feed bowl, and started with finely chopped lettuce after a week, to start rounding out their diets.
I would use what you have there with some added oats.
(Some think that the angel wing may be caused by something other than protein, FYI.)