We could not talk to him in group and get a group update. Each member of the group had to complete individually. The entire quest, once you learn the path, took about 6 minutes per person.
When I did this on my 2-box pair, I could only update one of them down at the Thexian camp. However, after I led Ignatios to his home, I finished the quest on the first toon and then hailed him with the toon that didn't get the update. He went through the dialog asking to be led home and when I moved a few meters away from the camp and back, I was able to finish on the second toon without making the run twice.
I had the same problem with the update when dual boxing except when I moved away from the Satyr Camp he depopped but the timer was still running. I found back at the original place but he wouldn't speak to me. So I deleted the quest and went back to G Fay to get it again. 12:03, September 27, 2010 (UTC)
55886 at level 77
56652 at level 76