The SSPX could always conditionally consecrate Huonder in the traditional rite, and keep it secret, preserving such things as a video of it, and notarized affidavits signed by witnesses, so that then Huonder could continue a traditional line of apostolic succession. That might not even trigger latae sententiae excommunication, in that in the eyes of Newchurch, he's already a bishop, and thus cannot receive a consecration that he already possesses. Then, when all of this mess is over, his traditional orders could be unveiled.
Better not say that too loudly, as Newchurch might suspect that the SSPX would do such a thing.