Really? Well get started, you have a billions of existing systems throughout the world to redesign to your specs.
You just told us what was wrong with your S and explained why there was no message. The door was not suppose to open when there is no 12V current from the battery. There was no message because the 12V battery had not failed. The battery is okay. Maybe its old enough on a '14 to be safe and replace now, but its working.
Yes, funny thing the car came back to life, right after the shaking moved at least one of the cable terminals on the battery or helped the ground strap. It had either a loose battery terminal or the terminal was corroded - LIKE ANY OTHER CAR COULD HAVE HAD. Maybe it will help to get/replace the existing battery. But I bet the SC is going to find either a loose terminal, corroded terminal or ground strap has corroded to the frame and lost ground connection.
You would have saved your self some less than 110% supportive remarks from folks here (including me) if you had added this to your first post.
The tow driver could have checked the battery for the loose or corroded post. Maybe he did. If he did and found neither was the case, then its a ground strap to the body that needs replacing. We've seen it before.
And a connection is critical to make it run, but Tesla and other manufacturers do not build cars with redundant system because they are not preparing them for a drive to the moon.