You mention that the Dungeoneers death has the ability to kill the team, Emii. So why not give them a slight dilemma? :-
Force the advisors to seperate from the dungeoneer in order to complete a task, leaving the dungeoneer vulnerable to attack and keeping the advisors nervous and on their toes because they can't help their team mate should there be trouble (which, of-course, there will be at least once

).
A potential scenario would be: The team need to enter a fairly enclosed space to gain supplies and continue their quest. 'Arrange' for the dungeoneer to enter first and suddenly be cut-off from the rest of the team (perhaps a door or sentinel character would be useful here)
As the Dungeoneer continues with the task in hand, the rest of the team have to take the long way around and meet him/her at the far side. This of course is complicated by the compulsary hoard of Goblins being encountered WHILE THE DUNGEONEER IS ALONE. The advisors will need to react fast if they want to survive in 1 piece... :o