Most stable for me was 2 OS drives 1 storage, sorry it'll have to be Windows file system.
I'd recommend getting into your bios and disabling features that push windows as it won't give you the choice to also take the Windows OS drive out of primary.
Install windows first on one OS drive, then Linux on the other.
rEFInd used to be the bootloader I used and stopped windows messing about with the boot.
What's the need for Windows? Is it something you can virtualise?
What is it with this world that we protect car crimes so much like nothing else gets consistent protection in western countries. There is nothing blocking vision here no loose surfaces he could have seen them for a mile which only leaves the driver at fault even if unintentional you have a social responsibility for the safety of others when you're in public. It's pretty obvious he did something that negated this. Riding with cameras is becoming as mandatory as a helmet these days