Found out hard way that it's impossible to get title now, unless your 80. [quest=13065]Ohanzee the Elder[/quest] is impossible to get to on normal, needs to be done on heroic. He is in Gundrak, in the same room as Eck, and tunnel can only be opened in heroic. We killed every single boss, and activated the statues and still nothing.
If you started the Wrathgate quest line, you will need to finish it to get to all the elders.
http://forums.worldofwarcraft.com/thread.html?topicId=14657045704&sid=1
I think they're saying that you can't be on the Wrathgate quest line and try to get the achievement, so if you haven't started the Wrathgate quests, you should be fine.
I think Air is referring to the elder in gundrak being in the "extra boss" room. This is not accessible unless the instance is set to heroic. Since you cannot do heroics until you are level 80, the Ohanzee elder visitation cannot be completed by a level 79 or less (whether you are on the wrathgate quest line or not).