Who I have the same questioned this topic

My daughter lost her iPhone 4 a few days ago. Now that we have no hope of finding it (battery was dead so Find My iPhone isn't working), I called VZ. They said someone had used it today at 12:20 pm. I checked My Verizon usage details and see no usage - voice, data or text since the day it went missing. Can VZ tell if it was powered on, even if no usage was generated?