I'm sorry, but the "Unreliable Narrator" excuse doesn't hold water in this case: Jackpoint is an online community, so the tiniest possibility that someone might get a fact wrong under a certain interpretation should trigger at least two people posting opposing arguments 
Which happens

. Occasionally there are the posters calling "BS" to a previous statement or going so far as to actually explain why they're wrong.
There's also the other GM tool which is that each book being timestamped (the moment the reader downloads the compilation) at a certain date means that the GM could decide that A ) a piece of information in the main JackPoint article is wrong and that B ) no one who knows that the info is false has posted information to argue against it by that timestamp date (either because they didn't see the article, were busy writing up a long argument against it, are busy trying to kill the person that posted it, have died, etc.).
There's a nice time frame for all the books (I'll call them cycles

)
Cycle 1: Prior events...the actual period of time that given events happen.
Cycle 2: Writing cycle...the time period where the authors are writing it, up to and including where FastJack invites them to post and writes his brief intro.
Cycle 3: JackPoint commentators...all the comments occur during this period.
Cycle 4: The Download...where you download the most current info (as of the time-date stamp at the beginning of the download/book.
Unless there are internal references to time within Cycle 3, then one can't really know how long Cycle 3 is. It could all be within the time it takes to read that section and post those comments. Even further, if a poster posts a comment in the middle of an article...and never posts again...the reader has no way of knowing of that poster read the entire article, let alone whole compilation.
But of course there's a diminishing returns on rebuttal comments equal to how widely known the error is. The bigger the error, the more likely everyone will see it, which increases the speed at which corrective comments fly. Little or obscure error in a field no one else is familiar with, few people will notice it, longer it can take for either someone (who knows, but missed it, hadn't gotten there yet, etc.) or someone who's researching the facts (like Snopes would) to point it out...and they may do so after "you've" downloaded the book.

You know, there's always been the caveat for the last 22 years that because the in-character material is written by characters who may or may not know everything, they could be wrong.
Just to refresh your memories: We are talking about maps, not in-character writing.
Hehe, the maps could be drawn by an in-game cartographer

. That's how the Forgotten Realms first argued their maps way back in first edition FR...that the maps were less accurate the further out from the Dalelands one went because "our" cartographers have less accurate information. Or maybe in SR an AI is messing with the satellite map overlays
