How do I install Windows 10 on Mac without removing the existing Linux partitions?
As far as I know, you can do it, but the order of installation should go like these:


  
  Install Apple's Bootcamp and use it to install Windows 10
  Use Windows 10 to shrink the Bootcamp partition, freeing up space to 
  Install Linux
  Install rEFInd as a Boot Manager for all 3 OSes
  


All details are provided by Rob Pickering: 
https://robpickering.com/triple-boot-macbook-pro-macos-windows-10-linux/