I used Unknown 2334's coordinates to put waypoints on my map. I walked along the waypoints and found him lots of times by spamming the macro.

The problem is the droprate though. It SUCKS. Don't let the 10% from Thottbot fool you, it's a harsh lie. The droprate is 1% at the very most. I kept killing them for 2 hours and only got one mask.

If you're gonna do this, be ready to spend a solid 2 hours on it. It's even more annoying without a mount.