If you aren't sending email to the recordset loop and you are just trying to refer to another recordset in your email body, you probably have to move back to your original format:
Plan ID: <?php echo $row_User['ID']?><br />
PO/Plan Name: <?php echo $row_User['skPlanID']?><br />
Name:<?php echo $row_User['skUserName']?><br />
Email:<?php echo $row_User['skUserEmail']?><br />
and just add this to the top of the email template:
<?php
global $row_User;
?>