Hope things are good.
Our historical experience with both naviseccli.exe for Clariion/VNX for block arrays, and SSSU.exe for HP Eva, is that when disks die on these platforms, their presence disappears from the CLI output we have historically gathered. On platforms like this, you will see OCI's changes view show a change showing raw capacity of the array shrinking, because it is as if someone unplugged a disk from the array, and ran down the hall with it, cackling maniacally.
I can file a RFE for us to look into adding that -fault CLI command. Do you have any example output of it from when a dead disk is present?
Another challenge for OCI is that sometimes arrays cannot tell us everything we need to know about a dead disk - it may not be able to report the model/capacity/etc of it.