I really enjoyed the game and if the page didn't outright told me there were no other endings I'd still be looking for them.
*light spoiler*
Especially with the letter.
The fact that you can go back and double check the letter to see if your list is missing something, and then it actually gives you extra hints and tips on what to do really gives off the feeling that it matters how much you pay attention and what you do.
So it's a bummer it doesn't actually pay off.