tvOS setup

I followed the instructions at https://apple.nextdns.io and when I try to add the profile Apple TV gives error 1004. I have the file hosted on my own site after trying icloud and google because they don't easily give direct links to the file, they give links to the page. (Grrr).

So I have the file hosted with the .mobileconfig extension. What am I missing?

As a side question, anyone know why if I have DNS > Router and router is running nextdns CLI  why Apple TV isn't already using NextDNS? 

PS we need tvOS tags added to the forum!