Short answer: CoQ10 has limited but encouraging early evidence as an add-on in rheumatic disease, while psilocybin does not yet have clinical evidence for rheumatism. There is no direct research on using them together.
For CoQ10, a small clinical study in juvenile idiopathic arthritis reported reduced disease activity and improvements in inflammatory and oxidative stress markers when added to standard care. Some small studies in adults with rheumatoid arthritis also suggest benefits on biomarkers and symptoms, but data are inconsistent and sample sizes are small, so replication is needed.
For psilocybin, most human research focuses on mental health. Preclinical and translational work suggests effects on the 5-HT2A system, NF-kB signaling, and cytokines such as TNF-α and IL-6, but I cannot verify clinical benefit for rheumatic conditions. Legal status varies and potential interactions with common rheumatology medications are not well studied. For general background on guided psilocybin sessions, see this overview.
Combination: there are no studies testing CoQ10 with psilocybin for rheumatism, so synergy is biologically plausible but unproven. Safety, interactions, and optimal timing or dosing are unknown. Until controlled trials are done, treat the combination as a hypothesis only.
Bottom line: early signals for CoQ10, no verified clinical evidence for psilocybin in rheumatism, and no data on the combination. I hope this helps.