Broken Quest: Defeat Rathbreaker

When I started fighting Rathbreaker, I was killed. On the second try, I killed his two minions by him while below the cliff. I came up and started fighting again. I ran back down off the cliff for him to follow me. He did not. When I went back up on the cliff to re-engage, he didn't move and his HP would not drop when I attacked. The enemies on the cliff and the hyena spawns still worked fine. I attempted to fix the issue by portaling to town and back as well as restarting the game by logging out and back in but nothing changed. At this time, I cannot complete the quest.