VBA with Excel and IE: Can't get the source right source code?

Question

I'm currently trying to automate my IE at work with VBA and Excel, because we have some repetitive tasks to complete in an SAP System which is called within the Internet Explorer.
So far I am able to start IE and navigate to the starting page of our System.

I looked on the source code from the Sap System to search for an id from a div (lets say its 'SampleID'). But if I try to click it via VBA I only get returned 'nothing'. So I tried to print out the source code via VBA Debug.Print to look at the problem. And here's the thing:

The source code that gets printed is completely different from the Website's Source Code. In the printed code for example is a iframe that I can't find in the website source code. So that's the reason I can't find my div and any other objects, because they are not in the code that VBA is searching through. Can anyone tell me what's going wrong? Why are the source codes completely different?

Sub stgGo(){
 Dim i As Long
 Dim IE As InternetExplorerMedium
 Dim objElement As Object
 Dim objCollection As Object  

 Set IE = New InternetExplorer
 IE.Visible = True
 IE.Navigate ("URL")

'waiting 10 seconds to be really sure javascript is ready
 Application.Wait (Now + TimeValue("0:00:10")) 

'printing out the false source code
 Debug.Print strHTML = myIE.Document.body.innerHTML 

 Set objCollection = IE.document.getElementsByTagName("div")
 i = 0
 While i < objCollection.Length
  If objCollection(i).ID = "SampleID" Then
   objCollection(i).Click
  End If
  i = i + 1
 Wend
End Sub