I totally get this point. My impression was that the complete instrumental understanding was predicated on the metaphysical understanding, making the instrument

I totally get this point. My impression was that the complete instrumental understanding was predicated on the metaphysical understanding, making the instrumental understanding almost incidental. So like, the resolution to the cargo cult wouldn't be to teach them how to actually build airplanes, but rather to first dismantle their religious hierarchies, "correct" their religious beliefs, forbid or prevent their institutions of knowledge transfer replacing them with modern schooling, forcefully replace their epistemology with a "modern" epistemology, possibly using violence, promote certain ideals and social norms, etc. It seems to me that then and only then, with the epistemological groundwork, can the actual planes and runways be built correctly.