Some news on this?
I got the same problem and test the grub workaround as i write.
(AND IT WORK!!!)
For me as linux noob, it is ~6GB lost linux space in every windows VM,
plus the linux install overhead. no exactly smooth.
Is it possible to only install GRUB from a live cd or somth like that,
and defining windows as first boot selection?
TIA and special thanks @Nucklez !