[Eskaliert zur 2. Ebene] Übersetzung von Germanized Checkboxen funktioniert nicht

if ( class_exists( 'Sitepress' ) ) {

    add_action( 'update_option_woocommerce_gzd_legal_checkboxes_settings', function( $old_value, $new_value ) {
        if ( is_array( $new_value ) ) {
            foreach ( $new_value as $id => $checkbox_data ) {
                if ( ! empty( $checkbox_data['label'] ) ) {
                    do_action( 'wpml_register_single_string', 'woocommerce-germanized', "legal_checkbox_custom_label_{$id}", $checkbox_data['label'] );
                }

                if ( ! empty( $checkbox_data['error_message'] ) ) {
                    do_action( 'wpml_register_single_string', 'woocommerce-germanized', "legal_checkbox_custom_error_{$id}", $checkbox_data['error_message'] );
                }
            }
        }
    }, 10, 2 );

    add_filter( 'woocommerce_gzd_legal_checkbox_fields', function( $options ) {
        foreach ( $options as $id => &$checkbox ) {
            if ( isset( $checkbox['label'] ) ) {
                $checkbox['label'] = apply_filters( 'wpml_translate_single_string', $checkbox['label'], 'woocommerce-germanized', "legal_checkbox_custom_label_{$id}" );
            }

            if ( isset( $checkbox['error_message'] ) ) {
                $checkbox['error_message'] = apply_filters( 'wpml_translate_single_string', $checkbox['error_message'], 'woocommerce-germanized', "legal_checkbox_custom_error_{$id}" );
            }
        }

        return $options;
    }, 10 );

}