The OP is correct. All you need to do is survive long enough to switch the offering. Target an Elite acolyte, Mark them to sic a ranger on them, then slip on by. The Ranger will lose but you will get by. Keep doing this until you can Mark the one by the urn, then switch it! If you are really lucky you may even get away before they notice you! Either way, live or die, go back to Enwar for the next quest.