Is there a way I can do a IF node, that says if this doesn’t load the normal HTML page that its expecting, and loads this instead, then try and execute the javascript in a function node?
I’d avoid running JavaScript from external sources at all costs. But technically, you can execute a string using eval().
Example Workflow
Now your specific decoded JS includes a reference to document which does not exist in Node.js (and neither does window. So this particular code would not work unfortunately.