Please can you provide sources?
Isn't the defining feature of a mystical experience that the participant feels that they had one (its a concept about subjective internal states, not an objective thing to measure beyond i guess self-reported surveys). Given that its going to be self reported anyways, i think the general acedotes about psilocybin inducing spirtual "states" is pretty compelling.
Anyways, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5772431/ is a study on the effect of psilocybin induced mystical experiences.
See also, Marsh Chapel Experiment: