VitalityRises

Hey guys, recently doing the quest Eyes of Glouphrie and I'm completely stuck. I am at the part where you have to kill the evil creatures (6 of them), however it says that I only killed 5. I killed one in Brimstails cave before talking to the King, I'm questioning whether or not that one counted? If not I went back to his cave and it's not there? Could someone help please? If it helps I looked all over, including in the Grand Tree floors and nothing.