Ready to give up :( ! Radio button...

[Taem]

Simple question, I hope:

How do I "click" a radio button from a currently open browser, not WebBrowser1?

Sample Code:

Dim btnClick As HtmlElement = WebWindow.WebBrowser1.Document.GetElementById("radiogroup0")
                If btnClick IsNot Nothing Then
                    btnClick.InvokeMember("click")
                End If

This code does not work when I load up Chrome (which is my default) and give it focus using the code below, nor with Firefox, IE, or my proxy browser. It only works if I run this code directly through WebBrowser1 in vb.

  'Give browser focus
            For Each app As Process In Process.GetProcessesByName("Chrome")
            Dim theHandle As IntPtr = FindWindow(Nothing, app.MainWindowTitle)
            If theHandle <> IntPtr.Zero Then
                SetForegroundWindow(theHandle)
            End If
        Next

My guess? I have to somehow declare the currently open browser as WebBrowser1, but I think they won't share the same controls so I don't think that will work. I know it's possible to "click" buttons on other apps with VB, so I'm 100% sure this is possible, but how?

BACKGROUND: I'm trying to get this working with a proxy browser and can't change the default browser vb uses to it if that's your first thought, sorry. I've spent the last 16+ hours of my free time trying to find an answer to this and am quite literally at my wits end; I've read through two different Visual Basic Step by Step and Teach Yourself Visual Basic in 24-hours, and so many pages off Google, I honestly don't know where to begin, but ironically I didn't find anything even remotely close to the exact issue I'm having, and hence I have no clue how to proceed. A little "hint" would be nice if you don't want to give me the code.

EDIT: The error code I'm receiving is, "NullReferenceException was unhandled"