For what it's worth, I had a similar experience - had an SSD configured as cache volume (creates an array with two raid0 (!?) volumes). Reset it to non-raid and all my data was still there!
From: Intel� Rapid Storage Technology — Delete a RAID 1 mirror without losing data
Intel® Rapid Storage Technology
You should be able to delete a RAID 1 mirror without losing data if the RAID 1 volume is the only volume on the array or the first volume in a matrix RAID configuration.
After you delete a RAID 1 volume or reset the hard drive members of the RAID 1 volume to non-RAID, you can access your data with one of the following options:
This applies to:
Solution ID: CS-022836
Date Created: 23-May-2006
Last Modified: 04-Aug-2011