Is there really no feasible natural explanation for inhomogeneities in stable magnesium isotopes in materials such as those found in, say, meteorites? How frequ

Is there really no feasible natural explanation for inhomogeneities in stable magnesium isotopes in materials such as those found in, say, meteorites? How frequently do scientists do such fine-grained nanoSIMS analysis of materials containing magnesium? If the answer is “not at all frequently,” is it possible that this is within the boundaries of natural variation in these materials? I want to believe, I’m just a bit frustrated by the lack of context presented alongside this interview.