This will likely require Execute a JavaScript in Browser action.
I prefer using the JavaScript querySelector function.
If you are not familiar with JavaScript, or need help, please post the URL to this page if you can. If you can't, then post the HTML code using the forum Code Block that covers the target table plus a couple of <div>s above and below, and I'll try to help get you started.
You can view and copy the HTML code using the Chrome Inspect tool. Right-click on the table header, and select "inspect".