What if we do not believe that a change in raw material source would have any effect on the product, because the alternate raw material is chemically equivalent and has identical properties?
I don't know which industry that you are in, but my experience with raw materials in the rubber industry was that any change in supplier had a noticeable effect on the final properties. We always had to make adjustments in the formulation to compensate.
For example, carbon black is >97% carbon with three main properties, particle size, structure and surface chemistry (the remaining < 3%). While different suppliers can closely match a specified particle size, their different processes result in different structures, which has a strong effect on the properties of a rubber formulation. The same with surface chemistry.
Do not make the mistake of thinking that material properties are solely determined by their chemistry.