Q: Lost iphone (not online) ...anything Apple can do?

At this time no, except to look for it as you would any other lost object. The only way to track an iPhone is if Find My iPhone has been activated, the device is powered on, and the device has an active internet connection. If any of those are missing, then you cannot track the device. Apple cannot do anything to assist. They do not track devices.

Hi,

What if your iOS device is off or offline?

If your missing device is off or offline, you can still put it in Lost Mode, lock it, or remotely erase it. The next time your device is online, these actions will take effect. If you remove the device from your account while it's offline, any pending actions for the device will be cancelled.

From here > If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support