@Alpha_95
I do not have experience with UEFI-Install in VirtualBox; just one or two times I managed to install it, but I had difficulties.
BTW, EFI-Install in VirtualBox is not so advanced as real hardware; for this reason I install VM in BIOS mode.
I had a look at your autounattended, but I didn't discover errors.
Only one difference: the type-ID of the WinRE-Partition is written with big capitals on your site, on my site is with small capitals.
Try to install on your SSD.