Unless we can travel back in time and shoot Gavrilo Princip before he shoots Franz Ferdinand, the Holy Roman Emperor will never sit on his throne again.
That said, keep the numbers coming. Not even the liberal Catholic apologists can make 2+2=5.
But Kaiser Otto lives, as does his son Archduke Karl. Catholic prophecy assures as that a scion of this line will eventually come to power again ("The Great Monarch" who is supposed to be a descendant of Charlemagne and together with "the Great Pope" is supposed to reform all things after the Three Days of Darkness, if you believe all that).
The Matthias Dom in Budapest awaits.
Otto's father, Kaiser Karl, is now a Venerable. Kaiserin Zita will probably follow.