So how do you unlock all of the player's Memories Gallery, just wondering?
Ah, it's misleading, but the stage four stuffed player image is not actually in the game currently (the immobility ending sequence always starts immediately). That was an oversight from how I designed the gallery menu.
In the next patch I will either remove that "?" from the gallery, or think of some place where the image can be used (maybe it can be shown during the ending sequence?).