I don't know how a program that converts an image into PDF treats characters. I believe that old fax technology made conversions of characters to code, cuz it sped up transmission speeds.
I saw one post, in one thread where someone said they had a "th" char on a daisy ball, but there are so darn many threads about this today, I'd be at a loss to find the post again.
Seeing the differences in the signatures finally convinced me, though I was trying to poke holes in the story for a good portion of the day today.
Nope, that's why it is called "facsimilie."