I’m trying to check out the Nya’lotha raid as I didn’t play when it came out but I can’t seem to see it. I went to both Uldum and Pandaria but it looks like it’s is phased or something because I can’t see the entrance.
Never did figure out what to do.
Some quests are available while others aren’t.
I just went ahead and started doing all the quests I saw and it seems to be helping.
Edit: Got it, just needed to progress through the story quest.
I was just about to edit my post, but I haven’t found anything that is being definitive. You probably have to progress to the point at least where the zone changes?
But here’s a good guide for ya. Good luck!
If you’ve already got the necklace, the auto-pop intro quest to start it? Saw this note on picking it up manually.