I am glad you have what you sought. To be honest I have watched your threads in a couple places and still not sure if I follow what you are trying to do? I think we have similar goals, but as technical as you are, I figure my solution was too simple and would not meet what you are trying to do
With that said I will tell you what I do, and I would love to hear the functional explanation for what more you are trying to do
I got a new RV, I refuse to consider any kind of satellite, or special mobile wifi service or mobile data plan. Not familiar with xfinity at all
So I bought a Nighthawk X4 AC2200 WiFi EX7300. When we travel; 2/3rds of time I can find a local free wifi that I connect the Nighthawk X4 AC2200 WiFi EX7300 to. Every device in RV or with 300' has internet access. I have Roku boxes on all of the TVs. We stream our cable which is YouTubeTV. In some parks we can't get free wifi or the service is too far away, so I simply turn on hotspot on my phone (T mobile). I connect my Nighthawk X4 AC2200 WiFi EX7300 to it, and presto all of devices and TV have internet
We watch movies with no issues. Truth be told; we don't watch a lot movies when in RV, but we can do so if we want.
Only things I wished theNighthawk X4 AC2200 WiFi EX7300 had or could do.
1. Automatically remember a previous Wifi ssid / password that I connected to. Everytime, I come back home and connect the Nighthawk in RV back to home network , I have to pull out the laptop to setup all over again.
2. Range 200 - 300 ft is max under ideal circumstances (but hotspot from my phone saves the day) I have yet had to pay a RV park their daily fee for wifi.
3. Allow a setting so the EXT extension on connected SSID defaults to use. I don't know why you want the SSID on source router and the Nighthawk to be the exact same? It can be confusing to know which you are connected too.
I no longer have to use ethernet cord to configure for new SSID. Not sure how that happened? Maybe a behind the scene firmware / hardware upgrade?
Let me know what I am missing and thoughts.