G-Safe won't mount

G-Safe will not mount.

Drives have not failed. They show as OK. Drive icon does not appear on desktop. If I daisy chain another firewire 800 lacie drive through it, the lacie mounts on desktop so the bus appears to be working. I also tried USB, without luck.

I have a spare G-Safe drive module that had never been used. Even though showing drives were OK, I inserted that spare drive and did a rebuild. It completed 100%. But still no mounting.

Also, I have three other G-Safe units. I have swapped these drives into the other units and get the same action. In Apple's Disk Utility the drive shows, but it will not mount and says to try running disk first aid. I don't believe that's possible with these G-Safe units because of the way they mirror in their own hardware. However, in trying to VERIFY DISK it gives this error: Verifying volume “A-OneG”

Checking Non-journaled HFS Plus volume.
Invalid node structure
Invalid B-tree node size
Invalid node structure
Invalid B-tree node size
Volume check failed.
Error: Filesystem verify or repair failed.

I've also taken one drive out of it's tray and into a separate SATA enclosure. Same deal. Will not mount. Shows same error in disk utility.

Anyone? I'm trying to avoid sending it in. That's a month or three process, as I've experienced on my other units.

Thanks!