Even the Supreme Court has accepted that the State of Washington was admitted to the Union on February 1889. David Darby will have a hard time making his claims.
On February 22, 1889, an act was passed providing for the admission of Washington. 25 Stat. 676, c. 180. On November 11, 1889, the President, as authorized by § 8 of the statute last referred to, issued his proclamation, declaring Washington duly admitted into the Union. 26 Stat. 1552.
Source: Washington v. Oregon 211 U.S. 127 (1908)
I have found the actual statutes. I guess David Darby may want to pay his taxes asap.