I need a declaration form or affidavit formatted so 1 witness on a will can confirm that both are valid, with notarization.
1 attorney answer
The RCW is being correctly applied. Since the testator is deceased you cannot use the standard affidavit that we use when signing the original will. What you now need to do is track down each witness and have them sign an affidavit that the saw the testator freely sign the will and that they to signed the will. If you are able to locate the witnesses, contact an estate planning or probate attorney to draft the required affidavit.
If you cannot locate the witnesses you will need to probate the estate intestate (without a will).
Avvo has a listing of estate planning and probate attorneys in your location. Most offer free initial consultation. Good luck.