That's not the hardest battle you will face though. That one comes in Tergothan Bay, the next zone. It's part of the mainline also. I forget the name, but it involves going in to the castle to look for Will. You have to fight a series of guard parties, and they hit very hard. Personally, I would try to reach level 85 before you get this quest and just transfer over. But, if you are stuck, you need to make it past the first group, and part way into the second, when the NPC shows up, even if in battle, talk to him to transport out and complete the quest.
i would not recommend this one, it will take longer to reach level 85 before you get someone to help you with this quest and there is not much time anymore before the server go down. if you play with your friend it should be much easier to do than solo.