If the 911 dispatcher can see the GPS location of the phone (I think this is the case?) then presumably they could geofence amusement parks and ignore any crash notifications where the caller does not confirm an accident happened?
Ignoring, of course, the potential for actual injury at an amusement park that could well need emergency assistance.
Better perhaps for the device itself to have the geofence and coding to understand when it's not actually been in/on a vehicle.