Hi,
The subject is generated with the line:
$order->mail->subject = JText::sprintf('NEW_ORDER_SUBJECT',$order->order_number,HIKASHOP_LIVE);
in the file administrator/components/com_hikashop/classes/order.php
If you want to have other dynamic data in the subject, you'll have to modify that line of code.
If you want to have the company of the user in CB, you'll have to load that from the CB table where that is stored with a MySQL query.
The exact MySQL query would be something to ask to CB support.
Just note that you can get the user id in the variable: $order->customer->id
It will be useful in the MySQL query to CB.