Aaron employed a ghost signer for many, many years TTM. The straight-legged "H" (lacking the typical loop leading into the crossbar) is a telltale sign.
I know DiMaggio's sister signed a ton of his mail at one point. Supposedly the story was Joe didn't understand the difference, and when he realized how it impacted collectors he started signing himself. At least I remember reading that somewhere many years ago. I believe that happened well before 1985 though. I think by the 80s Joe D. was commanding pretty high card show prices ($40 was a ton for a signature in the mid-80s
) so I'd doubt anything obtained TTM for free would be legit. That said, if this one isn't real, it's close, but I don't love the "J" or the "M."