2002 Mercury sable

I lost the key to a 1997 Ford Mustang call the locksmith had the key made but it wasn't the right ignition so I have two keys that can be programmed but my car was still won't start the locksmith told me that he thinks the module is bad at six hundred and something dollars so now I'm trying to run down what's wrong with it if you have any ideas please let me know the car started when I parked it and I think the man's sabotaged it so that my car won't be able to move from his property and he can keep it any ideas on what he might have done please let me know

the dealer may be able to cut a new key from the vin # $ $ $