From what Ive found out in my playthroughs, you need to gather the other endings like normal and bad endings to find the clues.
Thank you so much! That got me the silver clue but I'm still having trouble with the orange one if I could just get one more hint! :)
(EDIT: Nevermind, I was just getting the hint wrong, haha)
(EDIT2: ...and now I'm stuck on how to get anything but Shirr's Bad Endings A and B. The walkthrough cannot come fast enough)