Does anyone have an .APK for RIF Golden Platinum? I've heard it's working and want it back for a specific use case but it's obviously not on play store anymore.

And does revanced fix not letting you log in?

How exactly does this work? I just found about about ReVanced from this post, and I managed to remove ads from the official app using it, but all the patches I see for the third party apps are "change-oauth-client-id". What does this do?

Vanced is long dead. Try Revanced:

1. download Revanced Manager
2. inside the app go to Patcher>Select an application
3. check which version of YT is currently recommended (18.19.35 as today)
4. download that build of YT from APKMirror. make sure you're downloading non-bundle release (.apk file, not .apkm)

now the process varies whether your phone is rooted or not.

rooted guide:

1. install the .apk, this may require manually uninstalling current version of YT you have
2. give root access to Revanced in Magisk
3. go to Patcher in Revanced, Select application and pick YouTube from the list
4. select patches you like; do not select Vanced MicroG Support (you can use Default pack, just disable MicroG manually)
5. click Done (n)
6. click Patch, this will take around 2 to 10 minutes. your phone will stay awake and I recommend not leaving the Manager
7. now click Install as root
8. if applicable, go to the Play Store, disable auto-update for YouTube
9. also, to make sure you don't accidently update YT, use a file manager like Material Files create a text file called detach.cfg and put it in /Android folder in main storage (where data, media and obb are)
10. inside the file type out youtube's package name: com.google.android.youtube . you can do this for any app you like to stay non-updated
11. using Magisk flash Detach3 zip
12. done. YT will work with your current Google account and will not update. you can tweak the settings inside the app.

non-root guide:

1. after downloading the app skip installing it and go straight to Patcher in Revanced manager
2. Select application but this time click Storage in bottom-right corner
3. find the downloaded .apk
4. select patches you like; do select Vanced MicroG Support (you can use Default pack)
5. click Done (n)
6. click Patch, this will take around 2 to 10 minutes. your phone will stay awake and I recommend not leaving the Manager
7. now click Install or click the shashlik menu (vertical ...) and Export apk to save it and not repeat the process for other devices
8. when successfully installed either from Revanced or a file manager after exporting the apk, open the app
9. it will prompt you to install MicroG. it's a little plugin which allows 3rd party apps to act as official YouTube apps. basically minimal Gapps replacement. go ahead and install it
10. log into MicroG. use your regular Google credentials or create a temporary app password, especially if you use 2FA (which may break MicroG)
11. your new YouTube Revanced is installed alongside regular YouTube, as it has different package name (Vanced MicroG plugin does this by default). therefore there's no risk Play Store will force to update it and you can use both the official and custom app at the same time
12. go to settings inside YouTube to tweak the app
13. you can share the newly-created .apk to other devices and straight-up install it with any file manager.

Vanced has been dead for a while. ReVanced is the replacement.

This guide helped me https://old.reddit.com/r/revancedapp/comments/xlcny9/revanced_manager_guide_for_dummies/

Bro phones have that much RAM now? Holy shit..