These are chilling reminders that all of us are individuals, and we may react adversely to seemingly benign substances. It's unfortunate that your medical team has failed you so harshly. I've no advice beyond what you already know: don't do that shit again. Eventually I think your body will return to good health if you stay persistent with behaviors you know: eat well, exercise, do your best to stay actively clean. Do you foresee ever being able to return to your phd studies?
Honestly, I really can't say. As it stands, my intellect has been severely degraded; my ability to recognize extremely esoteric mathematical patterns and relationships and process the information in such a manner that actual conclusions can be derived from it is essentially gone. Without that ability, I have no means of completing my research project. I really don't know if it will ever come back. My brain fog and inability to process information in general right now really makes me question whether or not I'll ever be able to do what I was once actually very good at.
Truth be told, though, that's the least of my concerns. I could live well with less brainpower if I was just able escape the psychiatric torment, physical symptoms, and other non-intellect-related neurological dysfunctions.
Your writing seems quite eloquent and refined, and this may indicate that your thinking is perhaps more hopeful than you may think. Since you've appeared to have exhausted all mainstream medical options and have tried numerous supplements, I wonder if you might try just good ole psychologist's counseling? Maybe just talking about all of this to a paid, reasonably neutral professional might be one step along the way toward balancing whatever you've disrupted? I don't mean another naturopath or experimenting with possible harmful experimental substances like NS 189 or whatever it is. Maybe try something more conservative like good ole talk therapy to expose a few blind spots you may have. Not that talk therapy is a permanent do-it-all fix it -- just another short term step along the way to give you additional outside povs. For me I find therapy annoying and infuriating for answers to long term problems -- but in the very short term (like one visit, two visits) it's helpful.