To be fair, this leaker has a lot more credibility in general than just getting E3 stuff right
He leaked TMNT in Injustice, and even the fact that they were four character in one, far before they were announced. He also leaked Base Goku and Vegeta as DLC in FighterZ before they were datamined, and correctly leaked the SC6 and FighterZ Switch announcements. And then, of course, he knew Ridley and the "Ultimate" name before E3.
Obviously it's not to be taken as gospel, and he has gotten stuff wrong, but he clearly has SOME kind of source and thus that's why he's not just being ignored completely.
You're mixing in other leaks with his. ---
NNID, PSN, and GT: Waluigi1 DD:DA Pawn: Xekoben the support mage