1st thing is do not do any cleansing whatsoever right now. i'll add a caveat that if you had genius advice as how to cleanse you could probably make some progess but it would be very dangerous.
most of the therapies that you tried and were unsuccesful with were all cleansing.
from your picture, if that is you, you look emaciated.
the first thing i would try is hydrogen peroxide baths with a ton of salt added, perhaps a whole box of salt per bath.
the peroxide will start to oxygenate you and this will hopefully allow you to at least process some food.
you could also try just a plain salt bath as well. a half box of entire box of salt per bathtub.
adrenal fatigue and orthostatic intolerace plus the bad experience with the fir sauna indicate low sodium. with very low sodium levels, the body essentially shuts down electrically and you can't really do much of anything, let alone embark on severe diets or cleansing routines.
in the meantime, also you need to find some foods that your body will accept without causing too much disturbance. i am guessing some form of animal foods are required now to build yourself up. i think salty meat or bone soups would be a good start. have you tried any raw milk? or raw animal proteins?
some possible ideas would be well cooked rice with ghee and salt.
i would also look into the Blood Type Diet for some specific food ideas according to your blood type if you know it.
no offense to arn because some of those ideas are good, but herbs like goldenseal could be a disaster for you right now. also if you start bitter herbs in your state and try to cleanse the liver it could also be a disaster. for a person in a very weakened state, bitters can sometimes just aggravate a congested liver, sort of like poking a beehive, and not actually promote any cleansing. goldenseal is a very potent bacteriocide and you could likewise start killing off bacteria or fungus while your organs are unable to handle the die-off.
i would lean to a high sodium diet, balancing excess potassium with sodium until you startt gaining traction.
one thing arn said is right, only do one thing at a time right now, and nothing too drastic until you are sure that it is good for you.
you can look also into ozone therapy as it is very effective with cfs.