>> Could she have seen his signature on her divorce papers and thought that’s how Moore signed his name?<<
Yes, from the comments I’ve been reading most people think that is exactly what she did, no doubt enticed to do so by some Washington Post employee dangling a wad of cash in her face.
From what her stepson says about her I don’t doubt she could have come up with the yearbook all by herself. And Allred said “I don’t want to know.”