Does anyone have any thoughts on this?
The problem with this type of complexity (RAID) is when it goes wrong, it is difficult to fix it without the proper tools.
The Storage Matrix software will allow you to correct the drive array; ironically it is only available in Windows.
What you need to do is to acquire (borrow) another hard disk and install Windows on it, basic install will suffice.
Install all the Intel drivers and tools.
Connect your drive array and start Intel Storage Matrix (or whatever it is called exactly).
Now you will be able to see the drive array with a red X against the drives it believes to be compromised.
You will be able to reset the error status and the array should now be complete again.
If you can see the contents, you should be able to shutdown, remove borrowed drive #4 and boot in your array.
I had the same problem running Raid 0 in ICH9R.
Could not fix it or find any way until after I built a new install on separate disk then plugged in the array to format and re-use.
That's when I saw the error flags, reset them and it all appeared.
Hope this resolves your situation too.