It is possible that the people who stole the car also damaged something electrical in the process.
I have had an auto locksmith make keys without a working example to copy - just to prove that it’s possible.
Would want to be 100% sure the key coding is right, because there will be no signs in the car that it is wrong - no fault codes - no warning lights. Just crank no fire.
Imob inhibits fuel pump and injector pulse. If you have neither, then imob fault - which could be a key:ecu match issue, a key reader fault or even damaged wiring.