Egad! There is a double-hoax going on here! Notice that the teller of he Moon-hoax story sets it at the Cape of Good Hope, the home of the Dutch-speaking Boers. Perhaps that was because the actual story teller is
Hans Pfall, a dutchman, who, having used his story of a trip to the Moon to gain his freedom in Rotterdam, leaked a fantastic version of the rest of the story to Locke, his hapless dupe at the New York Sun, whose story knocked the story told to E. A. Poe off of the front pages. The purpose of the moon-hoax was to threaten a group of wealthy investors, from whom he hoped for funding of a scientific expedition. So he concocted a story that included elements of the description of the moon that he'd already revealed to them mixed with obviously fantastical elements, like Unicorns. This sent a message, "pay up or I'll make your investment worthless."
Sometime later, Professor Lidenbrock and his nephew Axel begin an ascent to the center of the Earth with a trusted guide: Hans (Bjelke). Why might we assume that this Hans might be, in fact, Hans Pfall? The volcanic tube they descended was probably not in Iceland either - Iceland's volcanoes are much to active; those details were likely invented to hide the true location of the great tunnel. I'd guess at a location somewhere near Nantes, France.
Think back to Pfall's letter in Poe's account; in it, Pfall informs his accusers that he got the idea to go to the moon from a chance encounter with a book on Speculative Astronomy. Then he adds an aside,
"in conjunction with a discovery in pneumatics, lately communicated to me as an important secret, by a cousin from Nantz".
An "important secret" in pneumatics? Unlikely. But what if the "important secret" wasn't about pneumatics at all, but rather a sample of Cavorite? (and if he has Cavorite, perhaps he has Vril as well!) Pfall, who thought that the voyage to the moon would be his last, surely took his books on Mechanics and his scientific samples with him on the trip. In the public account, however, Pfall suspiciously lists
no books in his ship's inventory, an unbelievable claim given the precision of his calculations on the way to the moon, or are we to believe that he is a savant as well, able to keep great amounts of technical knowledge entirely in his head?
I think we can deduce the presence of Cavorite in the construction of Mr. Pfall's craft by the obvious absence of a method of
propulsion in Pfall's description, which is otherwise quite precise in detail. Pfall is, by his own admission not a scientist, he is rather a tinkerer - no doubt this maker of bellows envied the skill of the blacksmiths who hired him.
This would account for the curious state of technology among the Vril-ya. That they have the technology to fashion fully functioning robots, and artificial wings of advanced design, yet they show no other signs of scientific advancement at all? The solution might be this early contact with Pfall himself, whose only scientific knowledge, and all of his textbooks, were on the subject of mechanics. The Vrilya apparently made the most of this limited knowledge, doubtless noting the design of Pfall's pressurized capsule down to the cross-stitch.
There are two things that concern me: firstly, the manner of Pfall's return to earth, and his real reason for doing so. These things are never revealed in any account. Secondly, the messenger who delivers Pfall's message at the very beginning of Poe's story sounds suspiciously like a Moblin - a low level minion of the Cthulhi. If it was a Moblin, we can assume that it escaped its subterranean servitude, bringing with it valuable minerals, and setting these events in motion; we can assume this because, were there other Cthulhi involved, Hans would have had no need or reason to employ Lidenbrock to reach the earth's core.
I believe, gentlemen, that Pfall is not above selling his peculiar knowledge to the highest bidder, and alerting our most dangerous adversaries to these dangerous secrets. That we haven't heard of such a thing yet happening is some evidence that we are not too late to prevent this disastrous turn of events from occurring and beginning a race (back) to the moon.