I would take this time to express my gratitude to Hermetian whose never ending questions helped uncover many more supporting data points that the document was created by a Xerox Work Centre 7655. We can even predict that the document was scanned upside down and subsequently reoriented using Preview.
I hope that Hermitian has learned from this experience as much as I have.
It’s time to write up my report announcing that we have found with a high likelihood the true forger of the WH PDF: A Xerox Work Centre 7655 scanner/printer/copier.
Good luck Hermitian and if you have any further questions or suggestions, please let me know. I always love a challenge.