Yes, it's possible one of your SSDs is dead.
Install Windows on one of your HDDs (no need to activate Windows).
After Windows is installed download OCZ's Toolbox and see if the toolbos can recognize both drives. If it only recognizes one then then other drive is dead.
If it recognizes both drives then verify that you have the latest firmware version on both drives, Secure Erase both drives, recreate your RAID array, and reinstall Windows.