Folders with R3Ds gone from External Hard Drive

[Jens Rosengren]

I had a folder of a project containing several R3D folders on a Freecom 2TB hard drive connected to my iMac running Mountain Lion using FireWire 800.
Earlier today I was going to grade some of the files and noticed that the whole folder had disappeared, which was weird, because every other file was there.
So I tried to show hidden files using Terminal, (defaults write com.apple.Finder AppleShowAllFiles YES), it showed some hidden folders, mostly stuff for the hard drive, but not my folder.

I then looked in my trash bin to see if I had removed it by mistake, it wasn't there, and I could see files I had deleted later than at the latest point at which I had seen the folder.
So I tried to use Disk Utility to repair the disk, it found some errors, nothing concerning my folder.

Would love some help, my Time Capsule hasn't been connected for a while, and around 80% of the project will probably be gone.
What do you think happened? Is there any way to solve it?

 

[Jens Rosengren]

Just for future reference, I tried out REDUndead, which I knew worked for Epic but was unsure worked for Scarlet. It is currently retrieving some of the files.
In some strange way it seems the files have been deleted. REDUndead is fantastic.

 

[Jens Rosengren]

Again, for others that bump into the same problem:
REDUndead also "retrieved" my files that weren't gone. Another solution I am trying is Stellar Phoenix Mac Data Recovery. It has found the folder, and another folder I hadn't noticed was gone and is currently reading clusters.