1. What difference does it make if the device stores any data for any amount of time. Until it can come online and transmit, there is nothing to track. And once it does come online, who cares about the legacy data since it can now transmit its current location.
2. The iCloud account at www.icloud.com will show the last known location for 24hrs. After that, no information is available in iCloud until the device goes online and updates its location. Talk to Apple if you think they should retain information for longer. At this time, they do not.
Your insults aside, my mind works very well. Your point about saving data is utterly immaterial to the OP’s question of how can they find their lost device NOW. And as the situation is now, there is no way to find or track an offline device by any remote means.
So if you think you’re offering anything remotely germane or helpful to this thread or the OP, it is you who needs to think before they post (especially when you have nothing more to contribute other than insults).