I am trying to change pdf for packing slips (on item fulfillments). I want to use the backordered amount from the sales order to display what is still on backorder. I am able to get many fields from

salesorder.item

in a list, but tranline.backordered or tranline.quantitybackordered both don't give me any results. Is there any way I can get this info into an advanced pdf?

Under the accounting preferences, Order Management\Picking/Packing section there is a setting for 'Show additional items on packing slips' that controls this