Bluetooth remote most probably communicates through Bluetooth Low Energy (based on reports from people that it should work fine for a year without charging)
Discovery mode is enabled in camera by double-pressing wifi button. Discovery
happens in .text:00011734 in app_ble. Its log is saved in
/tmp/fuse/1970-1-1.log. App expects BD address to begin with
20:73:80. If any BLE device with non-matching address is found,
invalid remote ble control device message with bdaddr and rssi is logged.