Ok, i found also that the revanced app has the plugin for youtube.
So when you download and patch youtube using the revanced manager one of the options is "Force Original Audio", make sure is selected.
Then when starting the patched youtube, go to Revanced Settings -> Miscellaneous -> Spoof Video Streams, and then select IOS Tv as default client. Then go to Revanced Settings -> Video and you should be able to enable the "Force Original audio language" option.
Reread what you have written:
You are 22yo, you have done an experience abroad (and it already place you above lot of ppl that didn't even left their own country), and i assume you speak at least a secind language beside your native one, then you managed to set up a new business, earning money, the businesses is successful, and the parents of this girl are trying to make you believe the opposite?
Well I think that you should be able to tell who is the failure.