"For a child has been born to us, a son has been given to us; and the rulership [the footnote for this word says "government; princely rule"] will rest on his shoulder. His name will be called Wonderful Counselor, Mighty God, Eternal Father, Prince of Peace."
Notice how this text is supportive of the full deity of Jesus Christ. That is something which is denied by the Jehovah's Witnesses. He is fully God and fully man.
A passage which says that Jesus is God can be found in a translation of the Bible that was designed to remove references to His divinity. Even the New World Translation contradicts the doctrine of the Watchtower Society.
If this is presented to a Jehovah's Witness, then he or she may very well be stunned or feel the need to explain away the meaning of Isaiah 9:6.