on your confirm page, there are hidden form elements to capture the shipping info that was entered on the chedckout page:
<input type="hidden" name="first_name" id="first_name" value="<?php echo((isset($_POST["shipping_firstname"]))?$_POST["shipping_firstname"]:"") ?>" />
<input type="hidden" name="last_name" id="last_name" value="<?php echo((isset($_POST["shipping_lastname"]))?$_POST["shipping_lastname"]:"") ?>" />
<input type="hidden" name="address1" id="address1" value="<?php echo((isset($_POST["shipping_street1"]))?$_POST["shipping_street1"]:"") ?>" />
<input type="hidden" name="address2" id="address2" value="<?php echo((isset($_POST["shipping_street2"]))?$_POST["shipping_street2"]:"") ?>" />
<input type="hidden" name="city" id="city" value="<?php echo((isset($_POST["shipping_city"]))?$_POST["shipping_city"]:"") ?>" />
<input type="hidden" name="state" id="state" value="<?php echo((isset($_POST["shipping_state_province"]))?$_POST["shipping_state_province"]:"") ?>" />
<input type="hidden" name="zip" id="zip" value="<?php echo((isset($_POST["shipping_postcode"]))?$_POST["shipping_postcode"]:"") ?>" />
<input type="hidden" name="country" id="country" value="<?php echo((isset($_POST["country"]))?$_POST["country"]:"") ?>" />
but there are no hidden form elements to capture the billing info that was entered.
the email can only use form elements that exist on the confirm page.