Quest: A Far Greater MenaceFollow

I'm up to the part when you have to find and kill Dryxl T'Rath
But there is no Pentagram ANYWHERE in this instance....

I'm in Retribution.... I've been in and out and in and out many, many, many times...
I've cleared out this dungeon many times over but the Pentagram just will not appear.
I've even searched the other 2 instances as well, on the off chance it was in them
(I have to zone into the regular version to to do two quests that wouldn't work in either of the others)

I am at my wits end here and NONE of the outline sources are of ANY help.
All they will give you are coordinates (which are meaningless) and a lot of bickering about procedure.