I believe that Psilocybin is legal in Jamaica, see https://www.mycomeditations.com/. Since it would seem that large numbers of people visit South America to attend Ayahuasaca retreats, one may assume it is legal there. And some religious exemptions exist for both Ayahuasaca and Peyote in the U.S., but even this may be a bit fuzzy as this certainly isn't widely advertised. One may also purchase legally, in all but a few U.S. states, Psilocybin spores; they become illegal once grown.
I've attended a couple ayahuasca ceremonies in the US. The first was very a peaceful affair. The second was not. There was yelling, screaming, the energy was all over the place. At moments, it felt very chaotic, like the top was going to blow off the whole thing. The facilitators (shamans) did an amazing job of holding things together, but that doesn't mean that I didn't experience some very intense waves of paranoia while all of this was going on. We were in a somewhat secluded place, but maybe not secluded enough to have made the screams inaudible to our closest neighbor. It was a rough evening for everyone.
