Good points as always.

Let me try to describe what I visualize.

A very large chamber of sulphur-saturated magma is undergoing cooling and differential crystallization. Chromite begins to crystallize/precipitate first and settles to the base of the chamber. There follows, perhaps closely after, the separation and settling of a Ni/Cu rich sulphide melt from the magma. DE1 represents the latter, DE2 mainly the former. Both are genetically related, but represent different times in the overall sequence of crystallization. Their present configuration is a result of structural deformation afterwards. Does this sound reasonable?