I really don't see a lot of negative fallout here for the DS fests. We're talking about two grown people (over 45) who both chose to engage in criminal behavior. She apparently decided on a career as a grifter, and he decided to commit first-degree murder. The DS fest was simply where they met, quite some time ago. They could have met at the Calvary Stampede and come to the same bad end.
For those concerned about firearms on airplanes, they've had to go in checked baggage only, unloaded, for a long time now. Harry Connick Jr. and John Popper (of Blue Traveler) are celebrity examples of people who got in trouble for "forgetting" about that handgun in their carry-on (both were arrested). The whole declaration process is done under the oversight of airline agents, so if this fellow had filled out the airline paperwork, it means he had no access to the gun at all during the flight.
For me, the creepiest thing about this story is the inevitable memory of a hotel that isn't there anymore, because we lost the World Trade Center to a few boxcutters.
