DNSB,
Just a thought. There is a free utility called ImageUSB from Passmark (free license for personal use):
https://www.osforensics.com/tools/write-usb-images.html
It allows "whole image" to be flashed to USB based disks. Can it be used to recover Xenophon's Clara HD by simply finding a "stock" image of the Clara HD and "reflash" back to Xenophon's device to overwrite the presumably corruption partition(s)? Can such an image file be downloaded from Kobo or elsewhere for recovery purposes?
What about devices without microSD but instead built-in storage? Can this recovery method work?