Would it be possible for you to post a copy of your confirm page minus the sensitive details? Since you are referencing the posted values it may be that these values are not being reset in the form on the confirm page so that they post to the page again for the order details and summary.
As for the undefined value error this is likely because of the values that are being passed in that are not set.
If you are not able to post this page let me know and I can open a ticket for you so we can exchange files in private.
