There are definitely Kush Boys robbing graves for bones but a cursory search does not find anyone who has forensically looked at the drug to see if it does contain bones.
here is a much more detailed story about the hell hole that is sierre leone.
https://www.npr.org/sections/goatsandsoda/2024/02/10/1229662975/kush-synthetic-drug-sierra-leone
Bodies might be dug up for formalin that is used to preserve bodies.
It is very easy to say just go buy a vial of whatever but that might not be the case in that location where many seem to be desperate and poor
Kind of interesting that no one has forensically looked at the drug to see if it has bones.