The fact they just kinda randomly pick which ending is “canon” is really confusing.  
Could’ve leave it up to interpretations…  
Like showing Shining City moving without using any methods from All the World’s Off Stage.  
Showcasing any scenes in the slide show from the “beginning” of any CYOA shorts in Happily Ever After Party instead of the endings.
 
IMO, this is not how you should approach CYOAs. Your choices should be contained inside one short. If you need it to have some consequences down the road, just make it one short with a decision tree.