Are you sure?
I know when I was born, and I have seen no evidence that indicates he was born in some other year.
I know everybody thinks they can get rid of the guy by finding the smoking gun, but you have to actually find the SG. (If it would even work then being still in question.)
There is an old science saw that applies here, “Absence of evidence is not evidence of absence.” IOW, that something is not adequately documented means only that there is inadequate evidence. It tells you nothing at all about what the truth might actually be.