Here's a link to the Rebuild 2 Fan Wiki page regarding the game's many endings. It has a lot of useful information for speedrunning.

https://rebuild-series.fandom.com/wiki/Endings_(Rebuild_2)#articleComments

I just added the second game in the Rebuild series, Rebuild 2 to speedrun.com!

Here is the link to that page. https://www.speedrun.com/rebuild_2