This site was built to compliment the existing NetSuite Professionals Slack Community by adding a means for members to easily find answers to common questions and to create a searchable database of those questions and answers.

NetSuite Professionals

Make a summary column that counts how many fulfillments a sales order has

Then add a matching summary criteria to filter that to 0

Also, if I'm not getting you wrong, you can add status condition in filter to choose only those sales orders which have "pending approval" and "pending fulfillment" status. This will get you sales order with no fulfillments.