A very interesting proposition with some interesting responses.
Having worked at an industry leading company that made implantable defibrillators, I have to say that there is no way that you can be sure that fibrillation is the cause of the patient's "medical event" without observing the heart rhythm with special instruments. All of the defib units that I have seen, whether a portable external unit or an implanted unit, has circuitry and software to detect that fibrillation is in progress. All of the units that I have seen also work automatically and will give a specific joule output to the attachment pads. Unless the group of engineers has instruments that can detect heart rhythm, they cannot know that fibrillation is present, and shocking someone is a bad idea. The reason to shock is to completely stop the heart activity so that the body will sense and restart natural sinus rhythm. The defib units, after giving a specific joule output will start monitoring the heart rhythm and will up the joule output and give another shock if the heart is still in fibrillation and repeat until a natural rhythm is detected. I think most units have a specific number of times that it will shock and then will stop further attempts.
With that said, if there were adequate pieces of electronics around and an oscilloscope, it could be possible to monitor and then defib, perhaps with 10-20% chance of success, which if I were the patient, that is 10-20% more chance than sitting around and waiting for help to arrive, because the longer the heart is in fibrillation , the less chance of brain survival that you have. With someone doing chest pumps, while others are trying their very best, the patient has a better chance.
Just my 2 cents...