You may call up US FBI or CIA department to help you recover.

Their technology is way better than any of the recovery data
companies out there.
They can even recover a hard disk that has been purposely destroyed
(hammered + acid pouring).
Don't ask me how, I've yet to understand how. From what I've read,
it's about those magnetic stuffs.
Other than that... you can try searching for softwares... in fact
nearly everything I tried barely works... all the files that
softwares managed to recover the files still ends up
corrupted...