Lost iPhone in Australian bush - how to locate? will pay if recovered

Trying to find a lost iPhone 7 - details below

• was on airplane mode
• says offline on icloud - apple have told me it must be out of battery
• the phone number of the lost phone has been switched to a new phone
• no Telstra towers near the location, unsure if triangulation is possible
• filed a lost property report, was told you can only triangulate a phone if someone is in danger
• unsure of serial number or IMEI

Is it possible to send this phone a 'ping'?

Is it possible to recover the 'last known location' if it has been more than 24 hours since it transmitted a location to find my iPhone? Do apple store this information?

We desperately need the contents of the lost phone and will pay for any info that leads to locating it.