It may have been destroyed by Aiwass iirc, but I suppose it is speculation regardless. On the last part though, nah, it WAS explicitly destroyed. The whole gambit was to force them out of the Hidden World (in which to do so they'd have to use a spell from one of their own to nerf themselves so that the "world" can actually handle their strength) and then he took advantage of said spell, reverse engineered it, and then nerfed them even more. This power null itself actually applies to another character, Coronzon, as well funnily enough. Basically being immune to everything Aleister could throw at her. It's not like they'd WANT to destroy the dimension anyway, since it can actually handle them passively existing in it. Any more than that, I don't think they actually fight in it. While Aleister actively attempted to destroy it.