I have 3 hikvision, 2 Xiaomi DaFang and a Verint one
More details on my github if you want some inspiration, or purely copy/paste, I won’t be offended 
I’m really confused reading thru this trying to figure out if you want to create a hidden group or just totally hide the entities from the display.
If you want to hide them then just properly put them in your customize.yaml. If you want to put them in a group then hide the group you need to create at least two groups - one will be your default view that contains all the things you want to see and the other is not a view and will contain all of the things you want to hide then hide the group.
If it was me, I’d choose the first (customize.yaml) option.