Remember the thread in Oct. 2021 about "Secret Stories of Doors"
by Sofia Rhei? The story is "a very clever story about a
man who works for the World Encyclopedia and inserts fake
information," as the OP characterized it. Now it would seem that
the story is not a work of SF imagination. It's reportage! The following
text of an email I sent to the Oklahoma Historical
Society says it all:

To whom it may concern:

If your holdings of a newspaper titled Indian Republican,
published between 1898 and 1907 are identical to what
is available to me through newspapers.com, then it
contains a bogus spoof issue for June 4, 1900. I would
appreciate any help you can give me in tracking down
its source.

Here are the details. In your newspaper catalog, the
entry is identified as

Title: Indian Republican
Begin date: 06/17/1898, End date: 04/28/1905
Roll no. 3005-267

In the contents list, note that there is only one
issue for 1900 dated June 4. In newspapers.com the
issue consists of only four pages, compared to
typically eight for the real paper, and has typefaces
that are obviously different. Its content is, well,
a little off. It does contain a serious-sounding item
that mentions a speech given by president Calvin Coolidge
on Dec. 6, 1923. I confirmed from the New York Times
archive that this actually happened. Therefore I surmise
that this is a clue to the earliest possible date of
the prank.

One has to assume that the fake issue was put there to be
found eventually. I happened to be researching Tutankhamen
(as his name was spelled then) in connection with the
forthcoming 100th anniversary on Feb. 16 of the opening
of his burial chamber.

Regards,
Charles Packer