Cassandra Cain was replaced by Alexandra Cain, a courtesan/assassin educated and sold by Cain to Earth-?'s Lex Luthor.
J'onn has been replaced by R'okk, a green martian who chose to freeze himself in an stasis field to escape what he considered the decadence of the Martian civilization, only to find a future where his species had died and monkeys ran all over the third planet, pretending to be sentient.
Tim has been replaced by a Tim who never went through Robin 120 and never fell in love with Steph, so the poor bastard still, mostly, trusts Bruce. He thinks this Earth *rules*.
Bruce has figured this out, but can't bring himself to care.