What do you eat for fat? I have done failsafe and the best fat source if you can only eat chicken is clarified butter but you need to do it yourself, the ones you buy in the supermaket are full of crap. Don't omit fat because you will need it for many things but on your topic of nutrient deficiencies, you will need fat to help absorb what nutrients you do manage to get.
i can sometimes heat my mushrooms up in a little olive oil and of course the chicken drumsticks have skin on them and that is fatty
i might heat up a pork chop later today with some mushrooms - they are fatty too even if you discard as much visible fat as you can
I can eat broccoli and celery too so may add some of that to the mushrooms