WDG2NC10000E wont start up

The firmware is contained on a partition on the disk.  As such, you’ve essentially bricked your drive.  It’s likely you’d need a sane MBWE2 disk to clone the firmware partition back on.  Short of manual cloning, you could try putting a sane drive from a working MBWE2 and letting the mirroring run its course to one of your formatted drives (if they were setup as RAID1).  Then take out the sane disk and pop your other original drive back in and let the mirroring happen again.