Is it possible to Chromecast a known url/website/video url from webcore via a routine or momentary button to a Nvidia shield?
The short answer to your question is “no”. The nvidia shield isn’t a Google Cast device.
It is though. It has Chromecast built right into it.
You cannot “cast” a url. You can only cast from an app that supports the casting protocol. What you are asking is not a “thing” and not how you cast something at all. It doesn’t work that way.
I ended up using fully browser and the remote feature to launch a URL to my Shield