Great info! I have recently had issues with my storage card, so I have been looking into the issue on my own, outside of PPCGeeks. I have stumbled across a very similar fix. You can use the same steps mentioned in the OP with a program called StorageTools developed by Softwinter. I was amazed at what happened when I Analyzed and then Repaired my storage card with StorageTools. All of my files appeared, although they were renamed to sequential numbered names. All I had to do was go through the files and change the extensions back to their original, which was sometimes a guess whether it was jpg, mp3, wav, cab, or any other various extensions that were on there.
One word of advice in addition to this great advice is: Make sure to remove all of this information from the storage card once you have restored it and save it to a safe place, ie. your computer. Then format the storage card, and then you can replace the files. I only suggest this because I did not do this the first time I restored my files, then within a few days the card became corrupt again and some of the files could not be recovered.
StorageTools