[I'm getting an Authentication Error, trying to post this, apologies if it posts multiple times!]

First, some clarifications.

Sounds like your client was a part-year DC 1/1/19 - x/x/19 and part-year OR x/x/19 - 12/31/19 resident.

Was the VA income only from a W-2 and only while the client was a DC resident?  VA & DC have reciprocity when it comes to wages, so they are taxable on the DC resident return.  Sounds like the employer may have withheld VA taxes in error.  If that's the case, you might not need a VA 763.  Instead you need a 763-S with Exemption 1 selected:

https://www.tax.virginia.gov/sites/default/files/taxforms/individual-income-tax/2019/763-s-2019.pdf

The bad news is I think these still have to be paper filed (with the W-2 attached).  The worse news is that this income is going to be taxable to DC without any DC income tax withheld so you probably have a big balance due and possible underpayment penalties.

To get ProSeries to not cough up a hairball, on the W-2 entry, enter $0 as VA wages and the full amount as DC wages (add an extra state line below VA).  Be sure to set up the part-year and non-resident stuff at the bottom of the Fed Info Wks (PY DC, PY OR, NR VA).  The VA NR Wks should pick up the $0 wages from the W-2, you may need to enter other $0 amounts but it should be easy to chase down any red boxes.  I'll leave DC vs. OR for you to figure out, but ProSeries does a pretty good job of pulling the data from the PY Wks.

Once you have that stuff sorted out, go into the VA state and see if you can find where to tell it to use a 763-S instead of a 763.  I don't have the software in front of me right now but it shouldn't be too hard to find.