The main problem is that admin_finish, the only route you have defined, returns JSON data directly. Laravel properly runs the index method and provides the raw JSON response when you visit that URL in your browser. The Blade file containing your HTML table and the JavaScript required to populate it is never loaded by your browser.

For two distinct jobs, you require two different routes:
One way to show the HTML page.
Your JavaScript needs to call one route (an API endpoint) in order to retrieve the data.