I have been struggling with Youtube\'s API v3 now and I can\'t get it work in the way I want. My goal is to load the latest videos from a selected playlist into my website.
I had the same issue .. instead of using the API to get the newest first (there doesn't appear to be a way to do this), why don't you just sort the videos inside your playlist first, then use the API which will return them in the order they appear in the playlist.
Something like this: https://community.tubepress.com/topic/5624-how-to-customize-sort-order-of-youtube-playlists/