Maybe some useful info here...
Today, there were 3 of us Chiron players on 6 characters (2 each). At 20%, just before the script makes everyone run away and the npcs pop, the game stopped responding. I could move around and my latency bar did not show any problems but Draekon didn't attack and everything just seemed like time froze. It lasted about 6-10 seconds. We thought that our pets probably had taken him to 19% and we were all gonna be dead when the server caught back up, but luckily everything unfroze just in time for us to run to our NPCs and finish the event.
Hope that helps,
Warbeat