I hate to prod and criticize, but do you have more up to date documentation regarding policy and netlogin? Like I said, I'm on switch firmware 21.x and EMC 8.x.
Q. Can I use netlogin and policy at the same time?
A. Yes, you can. Once policy is enabled you cannot configure your netlogin VLAN, plus the other commands outlined in the previous link I shared.
Here's an examples on how to configure Netlogin with XMC: