LOL! Yeah, that'll get him really far.
He’s right, of course. All of the public lands should have been turned over to the state, when the territory became a state.
But there’s no way the courts will agree with him.
He’s going to miss a few blackberry pickings with a defense like that.
Arguably he has a Constitutional question.
Oregon is not a Territory but a State so US Constitution Section 8 Paragraph 17 defines what land the federal government is allowed to own inside a State.
“To exercise exclusive Legislation in all Cases whatsoever, over such District (not exceeding ten Miles square) as may, by Cession of particular States, and the acceptance of Congress, become the Seat of the Government of the United States, and to exercise like Authority over all Places purchased by the Consent of the Legislature of the State in which the Same shall be, for the Erection of Forts, Magazines, Arsenals, dock-Yards, and other needful Buildings.”
There were no Forts Magazines etc. there.
Oregon and other western states may want to get in on this as it is a USSC issue.