Secret Puzzle of platforms with the Tome

Yes its the floating platform puzzle u need 3 ppl for it , to take the knowledge u have to be the one that climb up

User Maze is wrong.

You don't have to be the one climbing.
Whoever climbs, once they interacted with the cube, they will prompt the cube to drop down and everyone can talk to it for knowledge.

You can also do this knowledge with Lahn or any class , that can fly a decent distance without dropping off, on your own.
I have gotten mine today, alone, with Lahn. I activated the puzzle, went to vaha's head, climbed the wall to the highest point and used the flying skill to reach the highest platform of the puzzle and you can just pick up the knowledge and leave.

I posted two pictures for reference.
It's not super easy to make the jump if you're inexperienced. But a few attempts should be enough to drop on the platform. On Lahn you can use LMB to do a sharp drop downwards mid flight.
If you fail, you need to go all the way back through main road. But if you got no friends it is what it is.

https://imgur.com/a/t1sj2v2