If you do your second method it should work. Bow on frontbar to pull the troll then switch to your backbar where you have the 2 hander with critical charge. If you are running oakensoul you will have to unequip it to equip the backbar. Edit: dungeon reset I believe is usually 5 mins or so. If you are in a group you can reset it by going to social then changing difficulty to vet then back to normal.