Private TTS Network (AT+PNM=0)

I’m just playing around and curious about setting up a private network on The Things Stack (paid version so this is theoretically possible). My understanding is that I need to set Public Network Mode to 0/False on the end node (RAK4631), and then configure the gateway (RAK7268v2) to run as a private network. I’ve tried multiple combinations of settings I think are related to this in TTS but with no success. I’ve highlighted the 3 setting that I think are related to setting this up, but not entirely sure. Has anyone else had any success doing this?