if you are still missing the files, dont write anything to the card, mount it on your pc and run a file recovery program on it see if the files are there, normally files are not physically deleted just bits changed to hide them until the host equipment needs the space and over writes them or a program randomly over writes the "invisible" files. I am sure there is freebie software out there that can do it, i suggested same to a friend with a camera sd card issue and they managed to recover a heap of photos of it including some which had been deleted months prior.