I have no experience with hives but taking 12 adrenal pills may not seem like it is doing anything but it probably is not helping. Vitamin C seems to be key in supporting the adrenals along with plenty of sleep. I also eat protein every 2-3 hrs.
I am hypothyroid as well and use compounded medication for it but it has never caused hives. I'm sure you know what foods might cause hives. If you are low cortisol you will barely be able to get out of bed in the morning and have low levels of energy. I use end fatigue daily energy enfusion by integrative therapeutics which has lots of vitamins and minerals in it. It is berry flavored and added to water. It seems to help me.
Seeing that you have insomnia it is probably caused by high cortisol and I wouldn't be using adrenal cortex products or isocort. Ashwagandha is an adaptogenic herb that might help to regulate your cortisol; it doesn't happen overnight.