This is just a guess, but maybe coccidiosis and/or a bacterial infection.
So this 3rd "sick" turkey had different symptoms. It was peeping outside (2 1/2 to 3 Months old) when I went out to feed the turkeys and chickens in the early morning. Why wasn't it in the coop or tractor? I went over to check it out and it stayed sitting. I picked it up and put it down on its feet, but it could not walk and sat down. Keeping it privately on the back porch, away from all other animals, I fed it ground up hot chili peppers in its feed and in its mouth. One day after doing this, it seemed better, and stood a few minutes and walked a little. I was encouraged and kept up the chili peppers, but the 2nd day it seemed worse, as well as the 3rd day. It died last night. This morning I processed it and one leg was quite blue as well as a tinge of blue on the other leg. What happened? I have pics if you need to see them. Everything looked inside to me.