I wouldn't completely bank on those items being the exact same as that list, though it's possible. When looking at the Oops Wharf and Ghost Blue quests, they follow a pattern. That pattern is that they don't use drops required in other quests. For Ghost Blue, instead of Mermaid Cards it was Mermaid Scales for example. In Oops there were things like A Girl's Wish, Black feathers, and then new things like A Boy's Dream, Pirate Towel, and Golden Eyepatches. I would instead bank on new drops for mermaid little and the fish guardians (Or making use of existing but currently unused drops), possible new Witch drops, and a new dig item for Lethos. Thus far from what I've seen Lethos' initial dig request is a new item (Stone Ginseng in Oops, Copper Nora Stone in Ghost blue, etc).
That said, thanks much kale, as it still gives us a direction at the very least.