Was in the last patch, the Dev's said the gateway or something like that was glitched and they were removing it for villains until it was fixed. No date as to when it would be back either... which makes buying the DLC kind of silly right now =p At least it's being looked at I suppose. Hero's version of the T4 raids been glitched pretty much since day one, making you walk Gotham and such instead of warping there like villains do.
Theres a room in Mogo thats essentially a portal to nowhere. As soon as you walk into it you'll fall through the map, and if you somehow manage to get through the other side the rest of the map will have a doppler effect that makes it REALLY hard to know whats going on.