Thoughts on Old Tales (Spoiler Alert)

Here are my thoughts (speculations?) on the climax of Old Tales, with spoilers. In the animation, the space station, Cinderella walks down a corridor and picks up a fragment of something. What is it? I've been thinking this since I first saw it, but it looked like a fragment of Isabel's feather. Regarding the timeline not matching... there's a time slip element that hasn't appeared in Nikke yet. Isabel is... at Goddess Fall, but considering the situation, there are also question marks in the parts that later serve as references for the Heretics. Also, Queen's face, it doesn't look entirely unfamiliar... my imagination is running wild, ^^;;;