How to pass the SEQ_NBR into a query based user list

Does anyone know how to pass the SEQ_NBR to a query based user list in AWE. I set the user list to 'Use user as input' and 'Transaction keys'. Both are checked. The user list source is set to query with the query set to DUR_WF_POCMPBDRQ_PRJ_MGR:

SELECT A.SD_TEXT20_2

  FROM PS_FORM_SD A

  WHERE ( A.SEQ_NBR = :1

     AND A.SD_RECNAME = 'PO_CMPBDRQ')

I see the SEQ_NBR field from the form table in the Transaction Approvals Levels section in the Transaction Registry for the FormApproval process ID.

In the form design, I'm using the approver user list specified above.  However, when I fill out the form and submit for approval it shows there are no approvers found.  I'm not sure if I'm missing a step or if I can't use a query based user list to grab a field (operator_id) off the form for the approver list, filtering for the form name (sd_recname) and the sequence number.