@alphastigma
It's important to understand some basics: Cure firmware intentionally cannot boot the device, it's sole intended purpose when loaded to an otherwise-healthy device is to stall the boot process before loading essential files thereby re-enabling Mass Storage Mode. That's to allow any potentially corrupt files to be removed or as a last resort for a re-format to be done. However, a heathy device shouldn't show 'software missing' message when stalled on the logo screen with cure fw loaded. That's because the only way a device with bad firmware shows that message is if it's gone far enough into the boot process to find that the main system software (as Garmin correctly calls the firmware in region 14, i.e. the data flashed from fw_all.bin) is either incomplete, unsuitable/foreign, corrupted or missing completely. Perhaps if you used a faulty cure fw file, it might show that message which is an indication of a region 14 problem. BTW, there is only one dezlcam afaik, HWID 2141 and it indeed has latest fw version of 3.80. You've used the correct firmware if your device matches the fw's HWID: [Only registered and activated users can see links. ].

As you've mused, i too suspect there's a hardware fault in this case. The only other reason a device shows 'system software missing' is if there is physical flash damage involving region 14 and that of course is not repairable using software methods such as cure fw. The Updater.exe pop-up message in your pic also supports the flash fault theory as it's indicating it cannot properly write data to some region.

To be certain you should download the GCD again and carefully remake the cure firmware then reflash it. When 'system software missing' is showing the device should be automatically defaulted to preboot mode thus making flashing with updater more leisurely than before when you only had a few moments to initiate the flash after manually starting preboot. Because it's in preboot (showing in Device Manager) it cannot also show in Windows File Explorer which requires Mass Storage Mode or Media Transfer Protocol enable. Preboot/Garmin Mode and MSM/MTP are mutually exclusive as you probably realize.