I can imagine that it is quite possible that the husk would be removed first for commercially produced diastatic malt. I haven't been able to find out enough information about the manufacturing process to know.
In my case, I could crack the grains in my homebrewing grain mill and sift out some of the husk material before grinding to a fine powder, but I doubt it's worth the effort. Such small amounts of diastatic malt are added to a dough that it probably makes no difference. Including the husk probably just dilutes my diastatic power a bit. I'd have to experiment to establish appropriate quantities for my dough.