Congrats on figuring it out.
Perhaps this would also work:
function change_menu($items){
foreach($items as $item){
if ($item-> post_name == 'the-slug')/*replace "the-slug" with menu item post_name */
$item->url = bp_loggedin_user_domain() . '/events/my-events/?action=edit';
}
return $items;
}
add_filter('wp_nav_menu_objects', 'change_menu');