It's obvious the guy is joking with his mock-formal tone, and he's not exactly Jonathan Swift when it comes to satire either. He can't even spell Mary Magdalene. Pope Augustine, votre blague n'a pas déclenché un grand succès. I hope he speaks French considering his association with the Faux-narch.
I'd say the goal of this is to discredit Great Monarch prophecies. There are others out there like Charles Coulombe and Rama Coomaraswamy who call themselves "monarchists" as if someone is TRYING to associate the idea with eccentrics.
Some have tied in Great Monarch prophecies with the Rennes-de-Chateau group, the Priory of Sion; that this is a secret society plotting to restore the monarchy in France. This has something to do with Holy Blood, Holy Grail and the idea that there is a lineage of Merovingian kings descended from Christ and Mary Magdalene, which was apparently the blasphemous gist of Da Vinci Code, and that the Great Monarch will be one of these "descendants."
Pope Augustine is playing around with all of that in a lame, tepid way. It was already lame even in its more elaborate original form described above.