I am working to get a Business Event to send email notification when all POs (not just one) linked to a sales order are completed. 

My inquiry is showing SOs and linked POs with unreceivedQty information and I am using this as trigger condition.
I have tried using Raise Event for Group of Records by OrderNbr but the event is triggered when only one of the PO completed. I need the trigger only when all POs completed.

Note that I cannot add grouping into inquiry because it won't work in BE.
Would appreciate if someone can advise on this.