Non surgical butt lift with Radiesse?

I’ve seen many women get Sculptra for non surgical bbl with little to no results(including my niece which has spent over $7k) This is my reason for opting for a non surgical bbl with Radiesse. Should the Radiesse injector be someone that also does surgical bbl’s so they know how to place the filler and shape the buttocks? Because I notice most Sculptra injectors just place the fluid anywhere in the desired circled off or marked off area-not really sculpting out the buttocks