Need Help becoming a FuryFollow

I finally decided on what I wanted (Fury). So I went to see Mizzog in north Freeport and was then zoned to the wailing caves to kill the wolf guy (lvl 18). My problem is that he happens to be guarded by two lvl 23's and a lvl 25. I can not defeat all of them at once by myself.

I asked a group I joined to help and was told that the class progression quests have to be soloed. So basicly they told me if I couldn't defeat them myself I was SOL. Is this true? Or was I totally lied too? If its true how the hell am i suppost to defeat that many high lvls all by myself?
I might almost be lvl 20 but I'm the biggest newbie ever. Any help would be appreciated. Thanks.