I can't quite see how you can crash a plane and then not have your details recorded somewhere.
If you are entering and leaving on a gendec there will be a record of that.
If you had any hospital treatment that will have had a record.
Most countries the local police will get your details.
To get out of country you would have to fly out on a commercial carrier.
It should be reasonably easy to prove who was on the aircraft or for that matter who wasn't