You appear to be looking at the wrong BCD. Somehow you have got a copy on your backup drive, and that's the (inactive) one EasyBCD is looking at. You should be able to confirm this by altering something cosmetic like changing Name = Windows 8.1 to Windows 8. When you next boot, the menu won't reflect your change, because that's not the BCD being used to boot the system.
EasyBCD is telling you that the boot files are on Z, but Disk Management shows that the system booted from the Boot Partition.
Disk Management flags have the following meanings "boot" = "this is the system you're running"
"system" = "this is where I found the boot files for the currently running system"
"active" (on the first HDD in the BIOS boot sequence) = "this is where I started the search for the boot files"
"active" (on subsequent HDDs in the BIOS boot sequence) ="this is where I will look if I don't find something in the MBR on the first HDD"
Since you don't have a letter on the Boot partition, you cannot navigate to it through the Explorer dialog in your OP, but you should be able to useEasyBCD > File > "Load System BCD store" to start using the correct one.