This looks very much similar to an aspect of this problem for which I have a work-around but not a satisfying solution.
If you wait long enough, you’ll see various attempts to boot via PXE and HTTP. Eventually a uefi shell prompt will appear. At the prompt, type FS0: to make the following commands relative to the system disk drive. From there, use commands like ls and cd to find the .efi file to boot - maybe something like FS0:\EFI\ubuntu\grubx64.efi. When you’re in the right directory, you can just run grubx64.efi (or whatever the name is on your system) and the system will boot.
That’s all very well to do once or twice to check things are OK but not a viable long term solution. Instead, having found the location of the .efi file, add it to the front of the boot queue with the following uefi shell command:
bcfg boot add 0 FS0:\EFI\ubuntu\grubx64.efi "Ubuntu boot"
Then type reset to exit the uefi shell and the after restarting, the VM should boot.
Good luck - it works here; I hope it works for you too!
Nevertheless, finding and manually adding the .efi file isn’t a prefect solution but it’s a start. Maybe someone here knows the real solution.
chris