Like everything else in this fairytale world, its not realistic to think in the event of an earthquake all the family members could be calm and collected and gather their supplies. or that their electronics would work.
They are so out on left field its laughable. They spend time preparing for the large earthquake, yet give little thought to health and safety at the local level. For example, there are no emergency evacuation procedures posted at the local kingdom halls in case of fire. In the event of an emergency, no one knows what to do. But they have to make a big show for the big earthquake.
Since watchtower ever does anything out of a altruism, I wonder if they are getting grants for the government for instituting emergency preparedness among their ranks.