Came across this n=1 report, thought others might be interested too. The author has a subscription program for gut improvement, but I would think that a motivated/organized person could replicate the basics on their own if money was tight. No supplements needed... just circadian training, intermittent fasting, not eating at night, etc.
https://hackyourgut.com/2019/04/05/chronic-fatigue-syndrome-reversed-with-lifestyle-modification/
https://hackyourgut.com/2019/04/05/chronic-fatigue-syndrome-reversed-with-lifestyle-modification/