Should You Kill Ambrus or Drain Him in Blood of Dawnwalker?

Boyar Ambrus is the one in charge of collecting blood for Brencis in Blood of Dawnwalker, and if you want to take him down, you'll first need to disrupt his operations in the northern part of Vale Sangora. Once you make him angry enough, he'll challenge you to a duel, but before that, you'll get a chance to poison Ambrus, causing him to constantly lose health during the fight. If you're not sure what you're supposed to do after dismantling Ambrus' operation, or if you're confused as to why Ambrus isn't dying in Blood of Dawnwalker, here's a guide to help you out.