The present GB/FDS claim a kind of Apostolic Succession going back to the now claimed first appearance of the FDS in 1919.
I don't think anywhere is it made clear who made up the FDS then, but let us go along with the fiction, (in reality we know only Rutherford really ruled the roost) and assume there was a group of guys who were the FDS, how did they know they were chosen as such ?
There obviously is nothing in the WT writings of the time as all this is Noo Lite, so, if they did not know their Heaven appointed role, why would they carry it out, except by accident? and if so, how could they possibly produce "food at the proper time "?
They would, in their own minds, only be producing their own musings, which again, in reality, is exactly what Rutherford did.