NO Succubus, no kidding

Well, after a week, yes a full week, of haggling with WoW game masters about the ruins and the non-functioning 'Heartswood tree' I've given up the quest for the Succubus demon. I've tried everything and everywhere, in those ruins. Now let me get this right, the tree is on the right hand side, as you get a little ways into the ruins, right? It has three circular foot pads leading up to it, right? An open up 'dial' should appear, right? If this is right, then I'm out of luck.

Its a huge tree that sparkles with some warlocks around it. Very easy to see and it is not bugged I just did the quest a couple days ago.

I've done the Heartswood Tree on 2 realms and have yet to have any problems.. could be the issue with your realm.

I've noticed that not all realms will possess the same issues. On Sisters of Elune I'll often find camps where all the mobs are bunched together into one large blob (which means hitting 1 aggros the whole camp instead of be able to pull a couple off at a time) while on Moon Guard the mobs are spaced out as they should be.
Try replicating the issue on another realm and get back to the GM with more info.

Thank you for all the help. The problem was resolved. I had to visit the guy in the Barrens, and he re-issued the location, of the Heartswood tree. All is right with the world.