camped the upper left side near skyfire mountains of burning woods for 5 hours killing Gylton, and Entalon. Then a guild member came with me for a hour. But not once did Fabled Entalon spawn. I can't even tell you how many times i killed them both . I then ran along killing every wurm i seen along the back end of the zone, from ruins to ruins(east to west).
light blue to a 67... hits 326 max that i have seen.. soloed him many times to get friends alts gear .. very fast respawn .. easily tanked by a 67 druid ohh fire nukes dont land and my friends 43 chanter eventually landed slow on it.
Not so sure level is wrong, could just be under con. Friend and I were pulling along northern zone line. Both of us are 53 necros and easily pull all mobs in the area. The Fabled Entalon pathed straight through our pull spot, aggroed us and took us both down to 40% in about 30 seconds. With buffs, each of us had close to 4k hp. He was triple hitting for 326 and summoned. While he was dark blue at 53, I would say he fights like a 60+ mob.