Cmpa?

Does this look like cmpa? All over face, neck, chest and flares up when breastfeeding. Been there since a few days old. He’s had horrendous nappy rash pretty much since birth and no creams or barriers are working including anti fungal. Poops about 10 times a day and are green, sometimes yellow and frothy or mucousy. He’s gassy and cries when needing to poop but otherwise quite chilled. Gave up dairy soy and egg for two weeks, no improvement but now back on it and it’s flaring up more and more green poo. My supply is good and strong letdown so thought it could be that but doesn’t explain the rashes. Daughter had cmpa but symptoms cleared up super quick when I stopped dairy. He’s 3.5 weeks.