A galaxy 18 does not have a NVM to store the log, it retains it by a battery on board which if in good condition might hold the programming and log for a month or two as we have found, but galaxy state 48hrs retention and if the battery is knacked as soon as mains and battery backup have been removed the information has
gone.
QFA
If it was communicating via GSM to an approved ARC did the monitoring station get a close the night before the incident ?