You can try Disk Rescue or Disk Drill. I think they both run about $100. I think Disk Drill lets you do a test scan for recovery. It's likely all file names will be lost, but the files may be there. Just depends.
Thank you for suggestion.I took the help of a third party software, however that was a different one. Stellar Phoenix Photo Recovery Software did its job this time but i will definitely give Disk Drill a shot in near future!