Single price column was not added to template, added was just possibility. It's {price_withtax} tag you have to insert to Items table template.
NOTICE: in 2.0.3 is bug, this price is not shown right. Please, wait until next version.
Or you can edit file administrator/components/com_vminvoice/helpers/invoicehtml.php
and replace line 654 by
$replacement = InvoiceCurrencyDisplay::getFullValue($item->product_item_price+($item->item_tax_amount/$item->product_quantity), $this->currency, $this->showCurrency);