I'm a bit worried by the reliance on email to validate aliveness. If something were to ...happen... (ominous music playing in the background) it's possible that

I'm a bit worried by the reliance on email to validate aliveness. If something were to ...happen... (ominous music playing in the background) it's possible that such an entity could gain access to my inbox, allowing them to sidestep the DMS entirely, perhaps even gain access to its contents? Ideally this would require two or three separate methods to verify you're still alive. Or some form of challenge/response relying on at least two different mediums/communication networks/devices.