I looked into the NDI video, and it looks like a really simple barrier for entry. For example, I can just use an iphone to proof it out. The downside is that what /I/ want to do including the /hardware/ I want to use is not directly supported. iphone is great for proofing it out, but that's not ultimately what I want to do. I still want to try this, but it will take more experimentation.
How does it support all my hardware? Oh, I forgot about that. I got one of these.
https://electronics.sony.com/mobile/5g-iot-devices/portable-data-transmitter/p/pdtfp1
It has 2 SIM slots for different providers. I signed up with tablet plans for t-mobile and verizon. This will allow me to do /unlimited/ data streaming as an RTSP client.