Cronn earned the achievement
on September 26th, 2009 at 9:52 am
That was during Wrath of the Lich King, when the achievement was harder.
* Shen'dralar reputation was removed as a requirement in patch 4.0.3 (Nov 3010).
Progress is pulled in real-time from the battle.net API. The value shown here is either the current reputation or the one recorded by the achievement - whichever is highest.