More Info Hook

$arr_detail_page_tabs = geodir_detail_page_tabs_list();
if (isset($arr_detail_page_tabs['post_info']['is_display']) && $arr_detail_page_tabs['post_info']['is_display']) {
	$geodir_post_detail_fields = geodir_show_listing_info( 'moreinfo' );
	if ($geodir_post_detail_fields) {
		// Say something here
	}
}

Where exactly you would like to place the headline?

Try this code instead.

function geodir_before_post_info_content() {
    echo "<h2>Certifications</h2>";
}
add_action('geodir_before_post_info_tab_content', 'geodir_before_post_info_content');

You are welcome.