BDJ had a Backupper giveaway -- I look for it to be on GOTD soonish, since that's the way it usually works -- giving me a chance to create a bootable USB stick, fix it, and then test. From giveawayoftheday.com/forums/topic/471003 :
The fix is to go to the Windows\ Boot\ EFI\ folder & copy the bootmgfw.efi file, rename it bootx64.efi, and replace the file with the same name on the USB stick -- for a USB stick created in AOMEI Partition Assistant, that file is located in the EFI\ BOOT\ folder.