Windows 10 install on mid 2010 Mac Pro - "EFI boot" is not in startup manager
What can I say. If your Mac will not boot, then that is that. My 2011 iMac could boot Windows this way after a High Sierra installer update to the Mac's firmware. I assumed that all Macs would be able to boot this way after installing either High Sierra or Mojave. Either I am wrong or you made a mistake. 

When I originally posted this answer, the instructions FAT32 formatted the drives. This was changed to ExFAT after the October 2018 release of Windows 10. This ISO contains a file that exceeds FAT32 formatted drive limit of 4 GB per file. The April 2018 update does not have this problem.

If you can not get Windows installed using the method in your linked thread, then consider trying one of the older more complex methods. For example, see Installing Windows 7 or 10 Pro 64 bit without DVD or Flash Drive.