In Brisingr when Eragon asked Oromis about the Rock of Kuthian Oromis stated that the name "struck a familiar chord in his memory" but that he could  not remember why. This response brought to mind three random thoughts on the topic.

  1. The Rock of Kuthian is an Eldunarí of one of dragons bonded to the Forsworn that was disgorged prior to the Banishing of Names and was immune from the effects that resulted from the Du Namar Aurboda
  2. The Rock of Kuthian is the Eldunarí of Jarnunvösk
  3. Given the reticence of  Islanzadí Dröttning, Oromis and Glaedr had about reavealing Eldunarí it seems plausible to assume that there may be other information that they withheld from Eragon, Aya, Saphira and Orik