@frit As I mentioned previously this is not a FOG Imaging issue. You are using FOG in a way it wasn’t designed. That is OK because FOG is an opensource project you can use it in any way you can imagine. The FOG developers do have limited resources to provide support beyond the scope of FOG imaging.
With that said, I feel you are going about netbooting in the wrong direction. Right away I see two issues with your setup.using memdisk will restrict you to only being able to boot in bios mode. memdisk doeesn’t support uefi booting. If you use memdisk you need to have enough ram to hold the iso image and boot from it.
I have a tutorial on how to use FOG as a netboot server (again not as the FOG developers has designed) here: https://forums.fogproject.org/topic/10944/using-fog-to-pxe-boot-into-your-favorite-installer-images
While I haven’t worked with manjaro its based on Arch linux (which also I haven’t tried to netboot) but you should be able to follow the ubuntu workflow to get it to netboot. There is a tutorial on getting windows pe to netboot and that does work.