So I believe this isn’t story related in this version of the game.
Let’s start with nice part. Cure/free each move tracker so you could free Bryn, reload save and free Bryn again for achievement.
Now you are going to want to cure Benjo anyway because it counts as a memento towards the mementos achievement.
Freeing Bran is optional quest in Nadir:
The cure for Benjo follows a sequence of quests, some are same as Festival of Magic and some are new to this version.
First part of the quest is given to you as part of main story line and is going to TremelTree, Franir’s Lair, Tower of Dhur, and Anvirum Cavern. You will fight boss and collect item from chest behind boss.
Take these back to Professor on first floor of Owl Tide Library. He will request Purified Air and Spirit Sapling.
To get the Purified Air, you need to go to the traveling merchant outside of Suvia and talk to the hogbunny, but he won’t give it to you until you have done all the flower quests in first 3 zones.
For the Spirit Sapling, you need to go to TremelTree. From save statue, go east until you can go south after crossing barrel bridge. Follow south path at end and you will see friendly npc Shaman interact with.
You need to solve 3 riddles for him, after each riddle you need to go back to him to trigger next, and you need to “dig” items up as Taika.
1st riddle: as you leave shaman area, you will see a camp north of you, east of camp is a stump with mushroom on top. Interact in front of stump.
2nd riddle: start of zone has circular path around a pond, interact with ground on west side of pond( left side of road here).
3rd riddle: from circular pond path, you will notice a path going NE and one going SE. Go all the way to end of NE path and you will find a stump with mushroom on it. Interact with back side of stump.
Get Spirit Sapling from Shaman.
Take air and Sapling to professor in owl library and he tells you to grow it.
Go to boss area in TremelTree and you can interact there. Tree will grow immediately. Take item back to professor and he will make cure. Go upstairs and give cure to Benjo.