CHAPTER 3 SPECIFIC GUIDE FOR THOSE STUCK AT 95% or 96%.
Just a note to those viewing this solution to the achievement. I wanted to make a post instead of a comment as others may skip over the comments section of the other solution. So, to add to the solution already posted, or outline the importance of order of collectable selection for Chapter 3 and to maybe help those stuck at 96%.
Before entering the destroyed ship, move over to the smaller boat to hear a commentary.
Proceed to the next small boat shortly ahead of the first one you just saw and stand close for a second commentary.
Now enter the destroyed ship, turn the power on, and ensure you listen to the recorder below before exiting.
When restoring power to the camps, go into the tent with the red lighting and observe the hanging photos.
Proceed to the "organ" staircase and over to where you would find the water level markings.Observe the water level markings.
Proceed back to the staircase taken to the organ and look at the notes and tools in the makeshift workshop.
When you reach the second part of the camp, observe the mural on the wall above the tent with the piano and projector.
When you arrive to the camp, enter the tent with the piano and projector but DO NOT INTERACT WITH THEM YET.I found it extremely important to begin with the projector, otherwise it voids the achievement "I'll make a note of that..."
Using the right button on the projector, press over to the fifth slide.Ensure that you observe the slide before clicking forward or you may not be able to observe it after.
Once observed, proceed to the end of the slides and observe the cartoon character.
Pick up the note under the table, the calendar on the right wall of the projector and observe the floating rock next to the projector.Before using the piano, open the case to its right and observe the page to find out the puzzle clue.
Now use the piano found in the tent and PRESS ALL OF THE KEYS BEFORE ENTERING THE CORRECT SEQUENCE.
This should then pop the achievement for those stuck at 95% and 96% as most guides created on YouTube never outlined the importance of the bolded text above. Just in case those are struggling with the puzzles, I will link a video guide below belonging to Maka91Productions. Although he may have been a little aggressive in speed with this guide, I suggest 0.75% playback speed and to follow each and every thing he does, especially interactions. This, combined with the guide I have written above should help fix the issue that many of you, including myself, seemed to have.