You don't even have to find the accolites first. There should be an option to ask about the cure when you meet her, but you have to explore the swamp and find the statue before you are able to get to her.
I just did the section you are talking about. go to your home and hit study. there should be a new one. it is a riddle that it gives telling you kind of how to place the ingredients. However if you just want the recipe for one of the items needed, called Heat Occisia, it is 1-Angel Leaf 2-Red Pulp 3-none 4- none 5-Water Lily. Once you have all the ingredients for the Spectral Sirup (the medicine from the recipe under study) create it and go back to the shop keeper.