Haven't tried this for individual devices, but sometimes use different emails for different networks. Should work the same. Go to Notifications and create a new email notification. Can copy existing email notification and change to address. Then go to the settings for the specific device, select Polling tab, check Use Notifications, and check the notification you just created. This will override the default so if you also want email sent to the same address as all other devices, you either need to add cc. in the new notification or check both notifications on the device.