There is still hope, try and get a trial of r-studio and see if you can see the files after it does a scan. I've used it for similar reasons in the past succesfully on other people pc's. You should never cut and paste, but give it a go.
The only downside is in trial mode it will only recover small files, but it is a great product and the trial will give you an indication of if they are rescuable. Then buy it...
There are alternatives....
Whats the state of the NAS device? I take it half are on the NAS and half on the pc? If so you might be able to install one of the drives out of the NAS into your PC or a caddy and retrieve them. The odds are the NAS uses a linux file system though. Let me know whats what and i'll try and help you further if possible.