Some modified versions require an additional plugin (like MicroG or a specific tweak) to allow Google Account sign-in. If you'd like to move forward, I can help you by:
Modified IPAs like this are often associated with "tweaked" versions of YouTube, such as YouTube++ or uYouPlus. These versions are popular because they bypass the restrictions found in the standard mobile app. Key Features of Modified YouTube IPAs youtube 11499 ipa
These are the most reliable methods. You connect your iPhone to a Mac or PC and "sign" the app using your Apple ID. Some modified versions require an additional plugin (like
Explaining the between sideloading and jailbreaking. youtube 11499 ipa