There is also this, from the July 22, 1975 Awake!
"A citizen of the United States of America who desires to travel abroad will find the following oath on a passport application: “I do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; and that I take this obligation freely, without any mental reservations, or purpose of evasion: So help me God.” If an applicant finds this objectionable, he is permitted to strike this oath from the passport application, and he will not be denied the document on that basis.
A godly person also appropriately weighs matters from the standpoint of Jesus Christ’s statement: “Pay back Caesar’s things to Caesar, but God’s things to God.” (Luke 20:25) If anything conflicts with God’s law, the Christian cannot conscientiously swear to it. Yet he might take an oath to ‘support and defend’ the provisions of the law of the land that are not out of harmony with the law of God. Enlightened nations that grant citizens freedom of worship do not require Christians to do things contrary to their Biblical beliefs and obligations to Almighty God.
But how might a Christian ‘support and defend’ the law or the Constitution of a land granting religious liberty? By engaging only in proper and legal conduct that also harmonizes with the law of God. He can also do this by his spoken word, including the giving of truthful testimony in a court of law. No one can reasonably object to a Christian’s swearing to do something that God expects him to do, and relative subjection to governmental authorities is required of Christ’s followers.—Rom. 13:1."
Marvin Shilmer used to have an excellent blog, but I can't find it online now. Does anyone know if he's still around? One of his blog posts had an article on this very subject, and included a pic of Knorr's signature on the passport application oath page. So there's that.
I think the lady in California, as sincere and well-meaning as she may be, made a big deal out of nothing. According to the Society's written material, and the example of its leaders, she could have signed the oath without violating the official tenets of her faith.