I firmly believe that 2-butoxyethanol or a complex version of it such as diethylene glycol monobutyl ether is the root cause of these ailments and these other causes you name are most probably side things that it causes.  It is a multi-faceted chemical that harms multiple body systems/organs simultaneously 

It is an autoimmune metabolic issue, and many glands and organs are affected & including birth defects of many kinds ... cancers, too (It is a teratogen chemical).  ... so autism, leukodystrophies, growth abnormalities ... especially diabetes ...

Many, many things are autoimmune, too by the way 

LIVER?  Of course.  Too, if I'm right that the red blood cells are immature, then the computer analysis of 'how is the liver doing?'  What are the White Blood Cells, etc?  Will not read right.  You have to take some tests (many probably) as they otherwise may seem OK or not OK.  This is a big problem as so many medications say to check liver, and if there has not been a 'correction' then damage can be ongoing that is unnecessary.

WHY is it that some soldiers didn't get GWI?

I think it depends upon the job they had.  Those standing behind the missile launcher systems got sprayed with this.  (It is in rocket propulsion - maybe an ingredient in bombs to start with)  One soldier thought there was something like Corexit in the Arms Room .  Seabees would move the chemicals around & I would be especially concerned about moving Corexit (2/3 of Seabees interview of a 17,000 sample had the GWI)  Second hand solvent exposure is a big issue, too 

The literature says the chemical leaves one's system in 24-48 hours.  I do not believe that.  I call it the 'tornado' chemical.  Even if it did leave quickly, it leaves behind a great deal of health damage.  No one should die before their time for serving their country or being a hardworking person at home or for an employer.

Best help in my opinion is the glyconutrient food supplements and good nutrition.

Meds for the chemically poisoned can add to their chemical load and cause other ailments to start up.

Margaret