Yeah, unless they were doing some very high dosing or whatever they were injecting wasn't gold or had some other chemical, I don't think what I'm seeing online matches with what's being described.

Lots of mentions of gold miscoloring skin (matches) but almost none about psychological or neurological effects. Mentions of gold and gold salts being used and having some reactions (positive and negative), but no warning or mention of mental breakdown. Warnings of contamination from certain gold salts and non-gold heavy metal contaminations. In fact, one article I found claims gold doesn't even cross the blood-brain barrier? (https://sci-hub.ru/10.1080/10408444.2018.1513991:"The blood–brain barrier prohibits passage of most metal particles or therapeutic agents (Lansdown 2007; Gromnicova et al. 2013).")

Definitely seems like the gold thing is more a symptom then a cause to me but I ain't a doctor.