How do i start CWK exchange quest?

Better yet, those Elpam Magnets needed for the "Lost!" quest in Elpam's quests seem to follow the same formula that a lot of Crimsonwood Keep Part I follow- ridiculously rare drop rates; and worse yet, not super great spawn of Barnard Grays to get them from. The next part- "ReVersal", isn't too bad in terms of drop rate.

The magnets is the easiest part of the quest though... Took me about 30 minutes on my 4 characters that did it. It's quicker if you go to the hidden-street that only has barnard grays and a chief every so often.