im also having trouble getting the sidney image no matter how many times i reset! also how do you get the point tracker?
I don't remember if I got it after beating the game, or if it was there from the beginning, but it's pretty much that big Points button on the top right.
As for Sidney's extra scene, this is what I have so far (WARNING!!! SPOILERS!!!): https://pastebin.com/uWytq3Vr