Not sure this will solve the Status validation issue, but it will allow you to access the PO Last Receipt Date the way Madeline's post describes.
Step 1 - find the table Key
1.DFDM > Providex.ddf
2.Key No: ByName
3.Click on Key Scan
4.Find data table [Key] to change/modify: PO_PurchaseOrderHeader and select it
5.Change Key No. Primary Key
6.Write down the Key=[xxxxxx]
Step 2 - modify the table Field
1.DFDM > Providex.dde
2.Click on Key Scan
3.Search = Key Value (from step 1, Line 6]
4.From the list select the Key to change e.g. LastReceiptDate Key=000365000046
5.Click on the Edit button
6.Field Number = 20, Starting Position = 1, Length = 15 (the field to be change will be display, so the value can be change to: 0
7.Change = from 1 to 0
8.Click on OK and close DFDM
Step 3 - bring the field into VI
1.Create a new V/I import template
2.Select Table Name: PO_PurchaseOrderHeader
3.Go to Tab2 [Data] and notice the LastReceiptDate is now available.