gistfile1.txt

function ninja_forms_remove_csv_values( $value_array, $sub_id_array ) {
	foreach( $value_array as $x => $value ) {
		unset( $value_array[$x][0] );
		unset( $value_array[$x][1] );
	}
	array_values( $value_array );
	return $value_array;
}

add_filter( 'ninja_forms_export_subs_value_array', 'ninja_forms_remove_csv_values', 15, 2 );

function ninja_forms_remove_csv_labels( $label_array, $sub_id_array ) {
	unset( $label_array[0][0] );
	unset( $label_array[0][1] );
	array_values( $label_array );
	return $label_array;
}

add_filter( 'ninja_forms_export_subs_label_array', 'ninja_forms_remove_csv_labels', 15, 2 );