Tried factory resetting enough times that I lost count. The only new development since my first post is that, my device started to display the following message after every yea-many reset cycles.
Seeming like all I have left to try is to get an RMA from kobo... Given that the device has, ostensibly, been factory reset several times over - can I reasonably assume that my personal data has been cleared from the eMMC? Does performing a factory reset *normally* remove KSM from the device entirely?