It's unlikely that the drone relies exclusively on GPS. If the designers believe the red key to be axiomatically secure, it's not an unreasonable assumption fo

It's unlikely that the drone relies exclusively on GPS. If the designers believe the red key to be axiomatically secure, it's not an unreasonable assumption for them to say "We'll believe GPS while it's present. Only if it's not present will we fall back to inertial navigation" (or whatever). Obviously, a spoofed signal would be hugely problematic for that system. And yes, Occam's Razor does point to a crash-landing rather than a hack, but a GPS crack isn't unlikely enough to be completely discounted.