Comic Multiverse continuity =/= Live-Action Multiverse continuity.
Multiversal duplicates.
Earth-789 = Comic Multiverse version of Batman (1989) / Batman Returns / most of the Christopher Reeve Superman events occurred in Batman 89 / Superman 78 comics.
Earth-89 = Live-Action Multiverse version of Batman (1989) and Batman Returns events occurred, BUT Batman Forever and Batman & Robin occurred. NOT the Batman 89 comic.
Earth-96 = Live-Action Multiverse version of Superman I-IV, Supergirl (film) and Superman Returns. (Don't overcomplicate it, please.) Superman 78 comic events didn't happen.
SAME THING with Batman 66 and Wonder Woman 77 comics. NOT in the Live-Action multiverse. They've already trimmed that fat into it's own Comic version of that/those Earth(s).
I'm sorry if that's hard to take in, but I bet you they're doing that as to say "These stories still matter in their own way." For example, you won't see Adam West's Batman canonically kill Joker in the 70s in the live-action continuity; the comic one sure so no Batman show fans get upset that a version they grew up with killed Caesar Ramero's beloved Joker.