You can use this code example to customize the header row of your Table View to CSV export so it's different from the header row that's displayed in the View online.

add_filter( 'frm_export_csv_table_heading', 'frm_change_csv_export_heading', 10, 2 );

function frm_change_csv_export_heading( $heading, $view ) {
if ( $view->ID !== 65 ) {
return $heading;
}

return '<tr><th>Name</th><th></th><th>Title</th></tr>'
}

• Change 65 to the id of your View.
• Change the string that's returned to the HTML header markup and content you want in your CSV export.
• You can put an empty set of th tags, like in the example, if you have a column that is two columns wide.