Although I'd like as Milton says, to open this up for anyone other than the "Marked" and those who went to Tulam, that will be up to the GM I'd have thought.
Although of course, those who wish to attend should really have some knowledge of whats been going on in Kuhl and regarding the Poison and the Cult.
A lot of people InGame know different parts ( or possibly all ) of whats been going on.
If your character doesn't and you want them involved... talk to people, ask questions, listen to tales. The information isn't posted on any forums ( well, not mainly) , buts its out-there, InGame to be found from various Characters.
There is of course this, to be classed as a "general rumour" going around :
http://forums.layonara.com/dragon-st...gard-kuhl.html ....
... but thats minor detail and only a part of it.