I think this line:
$UpdateQuery->bindColumn("shawn", "c", "".WA_AB_getLoopedFieldValue("Shawn_".$wa_repeatcount ."", $WA_multipleUpdateCounter) ."?php echo $wa_repeatcount; ?>", "WA_IGNORE");
should be:
$UpdateQuery->bindColumn("shawn", "c", "".($_POST["Shawn_".$MultipleUpdateCount]) ."", "WA_IGNORE");
It looks like it wasn't properly changed when you updated from MySQL to MySQLi