The Second Trial

I started my level 20 paladin quest “The Second Trial”. On the second part of the chain, I spoke with Master Kelerun Bloodmourn, hit the orb in the building, and started the encounter. Due to having low weapon skill, I took a long time to kill NPC #1. About halfway through the second NPC, the rest of the NPCs despawned and I could not complete the quest. I abandoned the quest, but was not able to re-take the quest. I waited at the quest giver, and went back and interacted with the original quest giver, to no avail. When I returned to Master Kelerun Bloodmourn, I was still not able to reattempt the quest. If you could please take a look and let me know what has happened, that would be greatly appreciated.

Thank you,