Necropolitan
Hero
It's not canon.No evidence against it exists either, but more than that, it is explicitly canon at this point, though it can be easily inferred from 80s canon.
Elminster 333 isn't going to portal into Elminster 616's study to try to get aid against 333's giant baby skeleton Szass Tam's plan to eat all the other wizards which 333's female Manshoon is supporting for some reason.