Bleak,
They use the name "Jehovah' in the Christian Greek Scriptures of the New World translation ? that they published.
However in the Kingdom Interlinear of The Christian Greek Scriptures which they also published a word for word translation of the christian Greek scriptures the Tetragrammaton the four Hebrew letters representing God`s name nor it`s equivalent in Greek NEVER appear in the Greek text, nowhere do they exist.
So they lie when they say Jehovah`s name should appear in the New Testament It was never their in the first place by their own publication.