Mac Mini 2011, the missing Drobo and Disk Warrior

About a week ago I installed security update on my mini and forgot to eject the Drobo DAS before restarting. The DAS will no longer mount, Disk Utilities can see it but not repair it and the Drobo Dashboard can see it (my data is still there). Drobo tech support recommended getting Disk Warrior to make the repairs.

My Disk Warrior disk came in today but I'm having some issues with it.

I'm attempting to boot from the DW disk via a Apple Superdrive but the Mini just won't respond. Whether holding down the C key or Option key and selecting the DW disk the disk spins up for a few moments with the gray Apple screen then a circle slash pops up. I've tried this many times, even leaving it for a half hour to see it responds but nothing. To be clear, the OS is fine, it's the DW bootdisk that's giving me trouble.

I have a MBP that I could use to Target Disk to the Mini but is that going to help at all with the Drobo mounting issue? I'm not all that familiar with the software and the site and manual have very little information in the way of troubleshooting.

Nothing on the Drobo is critical. It's just my DVD and music collection that I've started to rip over the last couple months. I'd rather try to fix it before giving up, reformatting and re-ripping all the media.

Sounds like the optical drive in the Mini may be going out or the DW disc is bad. I haven't used DW in a long time but I don't think you need to boot from it unless you are trying to use it on your startup disk. If that doesn't work I would try to repair the Drobo from the MBP and then reconnect it to the Mini.

Another thing you might check is to first unmount all disks besides your startup disk and then in the Finder choose Go -> Go to Folder... and type in "/Volumes". There should only be an alias of your startup disk in there (and boot camp if you have that and didn't unmount it). If there are any extra aliases or folders then delete them and reboot.