geniuses
the levels of your milk's vit D are going to correspond to your blood's levels. but not exactly. with exception of alcohol, and a few other things, there is less of the substance in the milk, than in the blood.
women deficient in vit D make milk deficient in vit D.
unless you go toxic, your milk will have its levels of vit D restored to where they are supposed to be.
none of the professionals you are talking to have EVER been educated sufficiently in human lactation
Hale's may have some info, but i don't own one.