So I did a search, and I found something that somebody may have been talking about, but I am not sure, and I am going to post some SS.
I was exploring on my private server in normal hyjal (not the raid instance) and I found a cave that houses an instance, but with closed doors.
I don't know what this is, but it might be a possible new instance? In a possibly new zone? In possibly the WOLK? :hf2: