Hmm... That's where I got the quest from. I either forgot or mislead you. I haven't played the game for a long time. Sorry for wasting your time
Edit: I was right, you just have to talk to Lothar after pouring the essence
I need a specific item in addition to the minotaur essence or finger wait to have an item in the water
I think you have to talk to Haskell 1st to give you a list of trinkets that you can get. It usually gives herb of grace after getting the trinket but if this is the 1st time, you should talk to Haskell 1st