This app was mentioned in 7 comments, with an average of 0.71 upvotes
Ugh well that's rubbish. Only other thing I could suggest would be to use a video-audio converter and download the audio from the YouTube videos..? I have a converter app on my phone and it let's you select what type and quality of audio you need, you just give it the link to the video (can be anywhere, not necessarily youtube) and it extracts and converts to an audio file. Although I guess if you've been trying to get this for that length of time that may be something you've already tried but just thought I would throw it out there just in case you haven't!
Sorry for inconveniences.
Now The fixed version of MP3 Video Converter is on PlayStore.
https://play.google.com/store/apps/details?id=com.fundevs.app.mediaconverter
You can try this without having to download any programs.
Or get an app like this one on the playstore