Nandor mentions that the Macarena craze kept him too busy to complete his citizenship process, in 1992. Macarena was not released until 1993, and the dance craze did not occur until quite some time later, in the latter half of the decade.
USA naturalization applicants may choose to omit or change various parts of the Oath of Allegiance, if they explain the reasons why and their evidence is accepted. But contrariwise, it is freely optional to omit the final words "so help me God".