User Fox_exe had direction for 2nd gen unbricking that some have successfully used. Use at your own risk.
User Fox_exe repositories:
Main Repository: https://fox-exe.ru/WDMyCloud/
Second Gen: https://fox-exe.ru/WDMyCloud/WDMyCloud-Gen2/
Second gen directions:
English: https://fox-exe.ru/WDMyCloud/WDMyCloud-Gen2/_Unbricking_en.txt
Russian: https://fox-exe.ru/WDMyCloud/WDMyCloud-Gen2/_Unbricking_ru.txt
usbrecovery.tar.gz: https://fox-exe.ru/WDMyCloud/WDMyCloud-Gen2/usbrecovery.tar.gz
Alternate method files:
uImage-wdrecovery: https://fox-exe.ru/WDMyCloud/WDMyCloud-Gen2/Developing/uImage-wdrecovery
uRamdisk-wdrecovery: https://fox-exe.ru/WDMyCloud/WDMyCloud-Gen2/Developing/uRamdisk-wdrecovery
Latest second gen firmware: http://support.wdc.com/downloads.aspx?g=904
Unfortunately WD appears to have blocked direct access to their older firmware files.
WD My Cloud v3.x, v4.x and v2.x Firmware Versions Download Links
https://community.wd.com/t/wd-my-cloud-v3-x-v4-x-and-v2-x-firmware-versions-download-links/148533
