Thinking of doing anything manually in MS Office made me cringe a bit. So I offered to build him a VBA macro to place the photos for him, provided that he populate a folder with all the images he wanted, then he could hit a button, pick the folder, and get a PowerPoint presentation with all his pictures placed.
Anyone who's written VBA for PowerPoint could figure out how to do this in a trice, but here I've provided an unlocked PPT file with all the code you need.
It seems to work fine for me, and you can do what you want with it.
You can download it here.