Again, nowhere does it state that the British had already denounced the
document as a forgery prior to the SOTUS

Actually, you are correct.

The CIA had informed the British last fall,
just after the Brits released their "white paper" that the Nigerian documents
were forged, that they were (supposedly) signed by officials who were no longer
in power,
and that a US investigation into the matter
indicated the claim was a hoax.

I should have said the "British were already aware that the information was
bogus" rather than "the British had already backed off."

Score on this particular phrase:
"joe" 1. Gould 0.