Maybe I'm too late to help you but it might save some trouble for others :Is there any way to update whitout twrp or PC? Just with eu updater app? My PC ports seems broken and can't detect properly my device, sometimes it disconnects in mid flashing. Last time I suffered a lot trying to install eu
Before you flash anything that takes more than a few seconds (i.e. a fastboot ROM) on a Windoze machine, take utmost care to ALWAYS disable the "driver signature" mode and enable the "driver testing" mode.
See this guide for help : https://windowsreport.com/driver-signature-enforcement-windows-10/