Given the circuмstances, might it not be possible to contact the bishop, or whomever does his administrative work for him, explain the situation, and see if someone could be asked to volunteer to be sponsors, even by proxy if need be?
If I'm understanding the procedure correctly, while it is nice for a confirmation sponsor (or, for that matter, godparent) to be someone who knows the child, someone who would take an interest in both his spiritual and temporal welfare, it's not absolutely necessary. I know in the Novus Ordo, things get more "tutti-frutti" than that, laborious preparation, long-drawn-out procedure, "get up in each other's business", but that is their thing, not our thing.
I will welcome correction or refinement of my points, if there's anything lacking in them.