Finally, you mention how in your first years of illness you did not meet all the ICC criteria. The ICC criteria do include atypical ICC for those who do not meet all the ICC criteria.
The IOM criteria do not have stated provisions for those who do not match all their stated symptoms. For example, I have heard from people with ME who do not suffer from sleep issues. They would not fit the IOM diagnosis yet, do fit the ICC because sleep issues are listed as an option.