We Were Here

This is a 2 player online only co-op game.
One player plays as the explorer and the other is the librarian
You need to do 2 and a half playthroughs to get all the achievements
The game takes about 15-20 mins to finish a playthrough
You have to playthrough once as the explorer then once as the librarian
Then you need to play up to the dungeon for the last achievement
You need to do each puzzle perfect the first time for an achievement
You also need to do a play through without dying
My video is 18 mins long and it will guide both sides through simultaneously
The explorer does most of the work

For this achievement you need to solve puzzle 4 (Dungeon) as the librarian. See in video at 5:00

Achievement Walkthrough:
Timestamps
Invite: 0:40
Puzzle 1 (Eyes): 1:30
Puzzle 2 (Paintings): 2:50
Puzzle 3 (Valves): 4:00
Puzzle 4 (Dungeon): 5:00
Puzzle 5 (Chess): 7:50
Puzzle 6 (Spikes): 9:25
Puzzle 7 (Theater) 11:15
Ending: 15:35‬

The Librarian needs to guide the explorer through a maze. You do so using the Map on the table. To activate the directions on the map, you must walk upstairs and press the white switch.
Much easier to explain via a video
Here is a video guide:
*Video takes you to correct time-stamp (3:19)