Restoring an iPad/iPhone deletes all the photos - normally, one would sync the device before the Restore, which would back up the images. Unfortunately, your friend seems to have put all his eggs in a very fragile basket.
The advice to try recovery software on the card(s) is worth a try - he should stop using them immediately and try to recover from them (if he used them for multiple shooting sessions on the trip and filled them up, only the last set will likely be recoverable.
Personally when I travel, I take a laptop and several 64 GB USB thumb drives - those are cheaper backup solutions than extra CF/SD cards. The thumb drives and the laptop are carried separately, so I have duplicate backups if I need to reuse the memory cards.