I think that towing it to the dealer once it happens will be your best shot. Stay with the car and show them the no start condition. Stay with the car if at all possible to verify that they are actually repairing something. The act of disconnecting and reconnecting your battery may reset the computer, and correct the no start condition, but not actually repair your problem. If they say it's the battery, ask to be shown the battery testing - since you have electrical knowledge certainly you can also tell if a battery is good or not. You dealer may or may not go along with all of this, but it shows your interest in "solving" the problem, and they may go the extra mile in nailing it down for you.