SD card img created with dd is all zeros

A computer illiterate family member asked me to recover photos from an SD card she used in her camera. She went to fetch them from her computer when it informed her that the device needed to be formatted. She swears that she didnt proceed with the format and asked if I knew how to fix it. I use a Knoppix boot cd that I like because it comes prebundled with ddrescue and other tools. Plugging the card into my built in reader, it recognized the device under /dev/sdc however it didnt automatically mount. I ran the command ddrescue -d /dev/sdc /media/sdb1/test.img /media/sdb1/testimage.log The output suggested it ran perfectly fine. It successfully read all 16GB and reported 0 errors. When I opened the img file in a hex editor however it was 16GB of zeros. I wasnt sure if ddrescue was just silently failing at every read attempt and just writing a zero, so I also tried plain vanilla dd and got the same result. Everything about the card appears to be fine, it is apparently just empty. Normally I am used to when memory controllers on these cards start to go bad that they misreport the memory size or there are bad sectors but here it all just seems like a happy factory fresh SD card. Of course she is tech illiterate so i cant rule out that she accidentally zero filled the thing but I would think if anything she would have accidentally quick formatted it and blew away the partition table leaving the bytes at address intact. Is there anything I might be missing or doing wrong here or is the card just completely hosed?