Bmw 530i car cannot start

I have a 2004 bmw 530i and i uderstand that when a car is involved in an accident the car has a security system where the car does not start. I cannot start the car with the key, and i also checked the battery, the fuses in the back of the trunk and in the glove box and they all are fine. I also checked the starter with the tool to see if there is current running and there is. I try to crank the car and lost current or power from the wire that goes to the starter, also a minute later I checked the main line power that goes to the starter and there was power again. So my question is how do i find the problem thats blocking the current to the starter. The dealer told me that i need to buy a pyrotechnic wire(that typically burns when involved in an accident) so that the car will start again but i dont see anything on the battery that indicates that a wire has been burned.

If you can help me out and let me know what is happening, I’d appreciated so much.