I use grayjay. Downloaded from grayjay.app. will that be a problem ?

I have YT premium and I subscribe to a bunch of creators. So they receive a portion of the subscription, depending on the number of views.

NewPipe doesn't support it :(

That's good, but don't forget that the point is that Google's pearl clutching about security doesn't apply when they are making money. They'll sell you straight to scammers if it makes them money.