Well, as far as you are concerned, it is because they wanted someone experienced on it. But they did specify you or Marcus.
"Well now, Roan, if your activities on this mission go on far outside the literal remit of anything authorised by the Council, it won't be the first time you have participated in such a thing, hmm? And not the first time that others suffer for the errors of the likes of yourself..."
"To the first, it is part of my job, and to the second, I asked.
"And yes, I speak of Zeiton. Much as I am sure your leader does not speak loudly of his part of that disgraceful affair, it did happen and he was there. There too he was involved in... 'creative' interpretation of the directives of the Council. That mission was NOT sanctioned, yet he did not think to question his errant Master. No, he let himself be swept along, heedless of caution, and into disaster. I warned the Council. I told them most severely what would happen. 'Too late top stop you', they told me. Little wonder- Master Gundark had not the sense to stop and think of her actions. And who is it that paid? Did she? Did you? No. Toan'Feia, whose wise counsel you ignored in its entirity until too late... HE died. And tens of thousands of his people died. You didn't listen to him and now you will not listen to me! What will it take to satisfy you? MY death?
"Oh, how the Council would have loved to have sent Gundark here, if she had been well... but one of her progeny, in their eyes, would surely suffice. Well. I will not let the Order win. You will not access the Vault."
He leads you out away from Kuylen's tent- a light drizzle is falling from outside- and in back towards the city, where he has made lodgings in the outskirts.
His apartment there is not decorated with luxury, but it dsoes contain several artifacts, presumably that he managed to get out of the Sanctuary, which crowd the small room, aking it hard to get around. He settles down, wearily, on a short rocking chair.
"There is a document viewer in that far corner," he says, pointing. "It is an ancient mechanism for the safe observation of even more ancient documents. Be very carelful; the piece loaded into it right now is old and fragile."
Despite having a variety of functions, the viewer is not really much more than a magnifying device that keeps the source material under constant protection. Still, the document loaded inside it isn't THAT old, looking at the analysis settings. Well, 800 years is old by most standards, but by the standards of the Sanctuary...
The portion currently zoomed up reads- in firm and classic Standard-
"87 degrees Latitude... the exclusion zone around this area shall stretch to a distance of two hundred miles... no works or extensions of any type shall extend into this forbidden zone, nor shall civilisation ever seek to investigate this area, for it will bring nought but ill-fortune to the peoples of this world.
In return for the meeting of these conditions, the undersigned shall partake nevermore again to journey..."