We know that this achievement is broken, although it can only be that the tracker does not work, in any case I will be making guides with all the collectibles and I will tell you if collecting them all unlocks the achievement. There are some talking dead that you can't interact with, I don't know if they really count towards the achievement or if they are just a bug but I included them in the guide in case they fix this so I recommend having save points in each area of the game.
Vavilov Complex and Forester Village:
VDNH Complex And Plisetskaya Theater: