I have HomeKit with various accessories with 2 ATV4K's as hubs for home. This works well for my phone, even outside the house.
I invited my wife home, and she accepted. It has been added to all Apple TV's is fine, and its permissions allow control outside the home, but anytime you leave the main WiFi, nothing is updated.
Even when it is on WiFi, it says that the two Apple TVs respond, and "Home Hubs" looks like "Offline" even when it looks good on mine.
I removed it and added it to the house several times, all with the same result.
I missed something?