Stay out of the iPhoto Library in Finder! Changing anything there will cause iPhoto app to not be able to find your photos. Don't concern yourselves with what that file says, the only thing you need to be concerned with is what is in the app itself. In the app, the photos should show up by date taken, but if you need to change that, you can do so by clicking on "Photos" in the menubar, then "Adjust Date & Time". Just do yourselves and your photos a favor and stay out of the finder!