example.php

<?php 

add_filter( 'FHEE__EE_Export__report_registrations__reg_csv_array', 'tw_espresso_add_people_to_report', 10, 2);
function tw_espresso_add_people_to_report( $reg_csv_array, $reg_row ) {
    //Setup the 'People' column even if emtpy.
    $reg_csv_array['People'] = '';
    
    //Load the people add-on helper.
    EE_Registry::instance()->load_helper( 'People_View' );
    $people = EEM_Person::instance()->get_people_for_event_and_type($reg_row['Registration.EVT_ID'], 3); // 9 is the people type ID
    
    //Create an array to hold all of the peoples names.
    $peoples_names = array();
    //Loop through each person assigned to a type.
    foreach($people as $person ) {
        //Check we have an EE_Person object.
        if( $person instanceof EE_Person ) {
        	$qualifications = get_post_meta( $person->ID(), 'qualification', true );
        	if ( !empty($qualifications) && is_array($qualifications) ) {
        		$qualifications = implode(', ', $qualifications);
        	}
            //Add the persons name and type to the peoples_names array
            //This adds them to the CSV using the format - "{person_name} {custom field value}"
            $peoples_names[] = $person->full_name() . ' ' . $qualifications; // custom field
        }
    }
    
    
    //If we have peoples name, implode the array and add it to the CSV.
    if( !empty($peoples_names) ) {
        $reg_csv_array['People'] = implode( ', ', $peoples_names);
    }
    
    return $reg_csv_array;
}