Considering the starter uses its own self contained oil resovoir which is in no way shape or form connected with the engine lube system i fail to see how a sheared starter quill shaft(which is designed to shear in event of a overload )would cause a loss of engine oil, more uninformed speculation here i fear, further as said above had the starter been dispatched off maintenance with no oil in it it would not have lasted more than a couple of cranks at most