door ajar light stays on after shutting off the car

i would start with the wireing going to the door switch possibly during the repair a wire was crossed.possibly daamage to your body control module from the fire. fires are like flooded vehicles problems can be caused in multiple areas of the vehicle as circuits like nerves run through the whole car .if it is not to annoying i would say prob will be there forever. good luck. thanks for asking Billymac

is there a wire that we can cut to shut it off without effecting the rest of the car?

The only thing that i can reccomend is to remove the light for the door ajar . cutting any wires may cause other problems. hope this helps thanks Billymac