Data Rescue 3 for corrupt but not 'lost' data on raid5

Hi, I have a drobo with 5 SATA drives in raid 5 configuration. The software for it says all drives healthy, the diagnostic report came back fine for drives, changed data cables, ports and even enclosures but cannot get the volume to mount. My macbook pro can see the drive is attached in disk utility but cannot mount volume - suggests first aid but that will only ask me to format and repair.

So my question is - can I use Data Rescue 3 to rescue something that is not technically lost. I know the data is there because the volume has correct name and capacity indicators in software and on enclosure are correct.

Thanks in advance.
Vi