The problem is in a world of magic, science tend to lose, so maybe you'd think alchemy would be better than shamanistic practices, but its magic, so nope. I mean think a bit like Warhammer 40k Orks, I mean sure they believe that color cause effects... and while for everyone else it doesn't work that way, well for the Orks it does work that way, they believe purple is sneaky... so anyone nearby dressed in purple they'll basically be hidden even if standing straight in open day light, no matter if its the Orks themselves or a member of another race, and this effect will work for basically anyone around.
In a world of magic belief = reality, so being an alchemist with a scientific degree of practices versus a shamanistic folk practices, well guess what, it doesn't matter, either will work so long as belief back the practice, because belief is pretty much the driving force for the entire thing. So I doubt that potions made by an alchemist would work any better than potions made by a shaman, I mean sure potions can have funky effects, because their is a fairly significant chain of cause and effects related to everything from ingredients, to method of fabrication, to all the way to whatever mystical forces around might decide to do, it mean the effects of said potions might differ, but otherwise having some more academic education won't favor the alchemists when it comes to achieving results.