The best part was the press release he did. The "word" got all over the world. It was even in the euro Stars & Stripes.
You have the press release, it was on tv and print media, and just followed years of notice that the state preemption law was clearly established. In January 2010, the Lewis County Commissioners began discussion to update their codes for the parks because of state preemption. A "reasonable officer" would know about the legality of firearms in the park (open carry or concealed). The fact that #135 mentioned knowing state law, and the chief writing that they discussed it before in briefings, almost shows they clearly disregarded the OP's right to be free from an illegal seizure.
The officers report about the city ordinance and even Judge Buzzard acknowledging it doesn't shield them. If we look at Cox v Hainey on qualified immunity, "In considering the relevance of an officer's pre-arrest consultation with a prosecutor, a reviewing court must determine whether the officer's reliance on the prosecutor's advice was objectively reasonable. Reliance would not satisfy this standard if an objectively reasonable officer would have cause to believe that the prosecutor's advice was flawed, off point, or otherwise untrustworthy."
Still amazing to see that in 2014 you have officers who disregarded clearly established law on firearms in the parks and video recording of public officials. At best they dont pay attention, at worst they willfully ignored it all to deal with a person not committing a crime.