Elijah translates-EL(Elohim) is Jehovah,, Hallelujah= praise be to Jehovah.--All know the tetragramoton was in the Hebrew writings= YHWH or YHVH= the name in our language = Jehovah.YHWH is not Jehovah. As noted you do not have a single Hebrew Old Testament or a Greek New testament with Jehovah in it
The Watchtower adds to the word of God
example it adds the word other four times here
Col 1:15 He is the image of the invisible God, the firstborn of all creation;
Col 1:16 because by means of him all [other] things were created in the heavens and upon the earth, the things visible and the things invisible, no matter whether they are thrones or lordships or governments or authorities. All [other] things have been created through him and for him.
Col 1:17 Also, he is before all [other] things and by means of him all [other] things were made to exist,
And two hundred thirty seven times it adds Jehovah to the New testament without a single supporting Greek manuscript
Created-THROUGH him= another did the creating.