Probably because this happened back during the First Age of LOTRO (Shadows of Angmar) and the GM you contacted was hired during the 2nd or 3rd Age.
Originally Posted by Gurthrain
Or, more realistically, they are not supposed to help with figuring out quests, and if he did not know this arcane fact off the top of his head, then he just followed process (the bane of our existence) and said he could not help. This is old, old, info and not a likely candidate for "cheat sheet" info for a GM, and would likely be unknown to someone hired within the last several years.
Cener, Ingo, Rilibald, Hesred, Halras, Loringo
Arkenstone (ex-Elendilmir) - The Osgiliath Guard