no way to get out of the instance on murdunk's last stand, best bet is to drop the task once its complete. that will send you back out to ylatra the vassal. now on the other part of your question make sure you have completed Partisan of the korascian warrens, located in /achievements SoD > Quests > partisan of the korascian warrens, if all those are checked and you still can not purchase the merc check in your achievements under missions now on the bottom Hero of the Korascian warrens, you must have the check for Murdunk's last stand the other one the crystal bloom does not matter. hope this helps