Hello and welcome to the Planet! Have you had a look at our Videos section by any chance? If you see the menu of categories on the right and scroll all the way down you should find 'Yuzuru's Journey' – that section is PH's collection of English subbed interviews and documentaries that spans most of his competitive career. You will find a lot of videos that are only found here which are subbed by some of our wonderful members, and even some that have been removed from YT but preserved here. I would definitely recommend you start from there, you can also check out the 'Media Appearances' for more interviews/events outside of competitions. If there's any specific video(s) you are looking for you can add it to this thread for sure!
I think the index that you're referring might be the compilation posts made by @kaeryth? I think those were originally made prior to the existence of the videobox on PH which is now our main archive for videos that is continually updated.
For recommendations, here are some of my personal favourites (in chronological order):
2012 Spirit of the Athletes documentary
2015 Kenji's Room Interview (5 parts)
2015 Yuzuru x Nomura Mansai (YouTube)
2018 Post-Olympics JNPC interview (HD) / YouTube link
2019 Post Jnats 'Hanyu and Yuzuru' Interview (3 parts)
Bonus: 2020 Lotte Gum Commercial Making of