outlander

Background:car was stolen a few weeks ago then recovered(I hate to admit but I left the keys in it)When I picked it up at the pound the keys were gone
It's a 98 lumina and had a new key coded and cut for it at the dealer today but the car wont start.The key turns the ignition,makes the dash gauges/idiot lights turn on,and I can hear the fuel pump turn on but the engine wont crank(starter doesnt make any noise)

Is this key the wrong code?I had them cut a new door/trunk key and that doesnt fit any of the doors or trunk either.
Will the fuel pump prime even if the code is wrong?Trying to figure out if the key is wrong or if its something else that the thieves did to it........(ignition looks un-tampered with because they had the key)

Is it true that of you try to start the car without the right key it will erase the computer and make you have to take it to the dealer to have it re-flashed?