Right. Handwriting expert.
It would expose Hayes to liability for false advertising and be professionally suicidal for Hayes to hold himself out to lawyers (of all people) as a court qualified expert witness in BOTH handwriting and document examination.
But hardcopy documents and electronic documents entail two entirely different skill sets. You can't move from one area to the other on the notion that one is a "document" expert. It's like saying an electrical engineer can give opinion on a building collapse because he has expertise as an "engineer." No, an engineer who is expert in construction is still needed.
No digital document examination credential is claimed by Hayes nor would one be needed by Hayes to declare the image produced by the pdf file to be forged, IMO.
The latter clause is nonsense. Of course one needs certification as an expert in electronic processes and systems to be qualified to give opinion on a digital document. And I think Zullo knows this. It's one reason why he has kept Hayes's report under wraps. It has grifting value to him to point to it, but he knows the moment it's actually released and attempt made to use it in a legal proceeding it's going to get flushed immediately.
“But hardcopy documents and electronic documents entail two entirely different skill sets. You can’t move from one area to the other on the notion that one is a ‘document’ expert.”
You have resorted to the non sequitur logical fallacy: your erroneous conclusion does not follow from your premise.
Hayes can most certainly be a qualified expert in two separate fields, as am I (CPA and CFE).