to be able to create the order history, the customer should be creating the account before they place the order, not after. it's rather backwards to create the account after the order is placed.
as for the form element not having a value the checkout success page, that is to be expected.
the confirm page is set to post to itself, process the transaction, then redirect to the success page.
the form data is only available to the forms action page. once the action page is done loading or redirects to another p[age, the form data is not longer available.
there is no post being made to the success page.
once the success page loads and the session is cleared. there is no way to tie the order to the user
