My party visited the Cauldron Hill a total of four times over three adventures (blowing it up twice in the process), so I had to invent some benefits of doing this to give them. Disregarding all the stuff that I added to the campaign myself, they spoke to memory-blanked Kasvarina long before the ending of Adventure 5 (leading to some inside sabotage on her part in the climax of the adventure), had a chance of obtaining the personnel list (linking to some other Ob cells in other parts of Risur and to Kell's guild) and spare wands of Bleak Gate transition, grabbed some inventions by Tinker (mimicking the paragon Technologist features - mini-ray cannon, grapple hook etc), found Kasvarina's stone ring (that was after they realized its importance) and grabbed research journal of Alexander Grappa with detailed protocols of his golem creation techniques