SWIM thinks their bark has mostly DMT n-oxides and want DMT. Can you mix zinc powder in the bark during the acidifying cooking step to do this conversion safely, so, it will not go into the finished product?

seem like no one has any insights on this, does anyone know how to test to see if the zinc passes into
the solvent?

If you have some acidified, reduced aqueous liquid then it will most likely work. But it needs to be the minimum volume and obviously free of plant material, you cant stir the bark right.