You can pick up this quest after you visit Bartholomew during the Nature of the Beast pursuit. Return to the Lone House location, head down to the laboratory and rescue a guy in the trolls. Loot their bodies to locate a silver thingy and start the quest.

Either keep the whip to your self by simply telling Bartholomew relating to this (or lying about not finding the thing ) or return the thing to its owner, who’ll reward you with 1500 coins and 375 encounter. The quest is finished.

https://www.youtube.com/watch?v=SLGQH5RNTF0