It looks like one of the includes pushed down the page, try moving these lines of code:
<?php
require_once("../../WA_eCart/Adv_CO_Scripts/AuthNet_PHP.php");
?>
from line 332-334 to under line 19 so you should have:
<?php
$pfgbest->GetContent();
?>
<?php
require_once("../../WA_eCart/Adv_CO_Scripts/AuthNet_PHP.php");
?>