What a coincidence, I did that just yesterday. Failed the first time (I thought it was "fixed"; was on my Warden and I actually popped Never Surrender, so it took a long time for me to die to restart :/), the second time I just ran all the way as soon as Candaith started his dialogue back to Radanir - was wondering why it took so long, ran back a bit only to walk into 3 Oath-breakers, somehow managed to get out of combat and hurriedly leave the place.
Tl;dr: just run as soon as Candaith yells out "HOLD!"
(And later, I logged into my toon in Landroval only to find myself next to Candaith in the Lone-lands. CANDAITH CAME BACK FROM THE DEAD!)
[COLOR="#669966"][center][size=1]Mildford - R9 Hunter • Support - R7 LM
The Storm Crusaders • Gladden[/size][/center][/COLOR]