I've tried completing this quest (and the escort that follows it) on two of my lowbie alts over the past few days. Pengail is never there since someone is always doing the escort quest. A couple days ago, I waited for about 5 minutes at his spot on my Captain - waiting for another player to finish the escort. As soon as he spawned, another player came up and "ninja'd" him to do the escort. I waited about 10 more minutes (killing the named goblin in the area about 3 times). When Pengail finally respawned, another player ninja'd him.
I gave up finishing the pendant quest and the escort because I didn't want to spend my entire evening camping his spawn point.
Fast-forward to tonight, and I notice my Lore-master has the pendant quest. It's green, and it's the last quest for her in the western Lone-lands. I hike over to Pengail, only to find that someone's doing the escort quest. This quest will likely go unfinished on my Lore-master as well since she's nearly out-leveled it anyway.
I'm not sure what can be done, but I wanted to bring it to the Dev's attention that these two quests can be very difficult to complete.