This might be worth a try. The formalities for a marriage are detailed here on the US Embassy
website. Note that your ex would had to execute an affidavit before an American consular officer, or a notary public in the United States.
If she did it at the US consulate in Zurich they may have a record. They may not disclose the information but it could be worth sending an e-mail and asking.
US Consulate.
Something else that may be useful is that her name may have changed
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| The couple's name
Under Swiss law, the couple take the name of the husband as their surname. The wife may decide to keep her own name, followed by her husband's (without a hyphen).
In certain cases the spouses may be authorized to take the wife's name as their surname. The husband may then keep his own name followed by his wife's (without a hyphen). These two choices amount to a change of name for the husband, and a request providing legitimate grounds must be lodged. Authorization must be obtained before the marriage from the competent authority in the canton of domicile. The request for authorization should be drawn up with the assistance of the registrar. | |
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