Not a WA attorney but suggest you might try calling local bar assn for a referral.
The above is not intended as legal advice. The response does not constitute the creation of an attorney client relationship as this forum does not provide for a confidential communication.
Often times any time you receive a notice from a state agency they will describe in the paperwork you receive how long you have to appeal and who you appeal to. Review that option first. If NW Justice Project has agreed to help then be persistent. They will work hard for you but they are also very busy. I suggest calling them back or going to see them to get them re-engaged in your case. If you are not satisfied with their service you can always retain your own attorney to assist you.
Providing this general response does not create an attorney client relationship.
Do not wait for an attorney to review your case before you respond to the paperwork from DSHS. If you're not sure what to do, call or email the investigator who issued you the paperwork threatening to garnish wages.
Also, inadequate service is NOT a defense in administrative law. The deadlines are very strict, and the clock starts when the paperwork is MAILED. The agency does NOT have to prove that the paperwork was ever even received.
Very few lawyers know much about administrative law. Before you hire any lawyer, ask which provisions of Washington Administrative Code will govern your question, and whether or not the firm has handled similar cases with the agency that charged you with an overpayment.