Find Bugluk at ( 1577, 457, -2 ) /waypoint 1577, 457, -2, hail him, and finish the conversation
Return back to Nesbit at U.J.L. with the new information
The boarfiend costume will cause the boarfiends to turn non aggro (they will view you as an ally); even attacking a boarfiend will not break the illusion so you can kill at will without drawing social aggro! So this would be a good time to pick up and do Lore and Legend: Boarfiend.