A suggestion: After you complete the Sad Ghost's quest with the Dried Rose in your inventory, a second dialogue pops up and asks if you want to hear more about the Rose (and learn if it's cursed or not) or go on your way with a token (a rose petal only available if you get the Rose before meeting the Ghost).

Since using the Rose requires talking to the Ghost, it seems like they might have such insight into the artifact. Just an idea. It crosses my mind every time the Rose drops before I meet the Ghost.