>>33847038>>33847039IIRC according to that chink girl from Bulbapedo who used to translate the Riddler's posts, after that "leak" was posted here, someone saw the Riddler and his friends talking about it on a private conversation. They apparently noticed that some things were accurate.
As you can see, all of this is basically a "someone I know told me that someone heard someone saying that the leaks were legit" situation.