So ... I've never seen it proven that the Church would defect if there are no longer any bishops left with ordinary jurisdiction due to direct papal appointment. Just as the papacy does not formally defect when it cease to be materially occupied (a different use of that distinction), because it continues on in potency, I don't see why the same cannot be said of ordinary jurisdiction. Bishops have that potency to hold ordinary jurisdiction by virtue of their Holy Order combined with being Catholic. So long as that potency remains, it's no different than saying that the Church and the Papacy do not defect when vacant.
During even a "normal" interregnum, it's Christ who formally supplies jurisdiction to the bishops who had been appointed by the deceased pope ... and one could make a case that this mode of jurisdiction is not "ordinary" either, since there's no Pope supplying it. Of course, Father Lavery CMRI ... rejecting this common understanding among theologians, that Christ, the actual Head of the Church, continues to supply jurisdiction in the absence of a Vicar or, for cases of Sacramental jurisdiction, "the Church" supplies ... rejecting these commonly-held formulae, Father claims that all jurisdiction must come from the Pope, not the Church, nor Christ ... and so, basically, he says that it's the ghost of Pius XII that's continuing to provide jurisdiction. Of course, the fatal flaw with his theory (among the general absurdity of it), is that ... well, uhm, Pacelli is no longer Pope, since he's dead. So Pacelli cannot supply anything to anyone, since "nemo dat quod non habet".