HDD won’t recover PDF Files

Acrobat could not open __ filename ___ because it is either not a supported file type or because the file is damaged.

I found some .pdf files doing a raw recovery from Ontrack and receive similar issues when trying to open these files (I tried to match some up based on file size.

So far I haven’t opened one file which makes me think the drive somehow scrambled all of the data. Any other recommendations?