The one who wrote the piece was the great-grandson of the alleged witness.
The piece written did not see the light of day until after the writer had read a summary of Sitchin’s claims in 1983.
The implied chain of transmission is this:
Humphries Brewer → William Marchant Brewer → Helen Pattengill (née Brewer) → Walter’s mother → Walter M. Allen
Anyone who knows anything about the oral transmission of family legends knows how iffy this is.