Did you get the Deputy’s name? Sno Cty Sheriff, WDFW and Snohomish County Parks and Rec (the parking lot is owned by them plus DNR) have an open investigation ongoingI just talked with a Sno Co Sheriff's officer who was in the parking lot at C-Post testing a drone. He wasn't on duty the day of the incident and hadn't heard about it. He said he'd inquire to get the details. He lives just a couple miles up the highway. He also said that there has been lots of break ins there, and alluded to other sketchy stuff but didn't give details.
I just live a few miles from there myself so this concerns me. I've only parked there a couple of times (actually I parked down by the gate, not where the parking lot is now) since it was gated. One of those times was with my wife.