It seems that the only supported Google Earth API is the JavaScript API. Therefore, your approach to implementing Internet Explorer for this sounds reasonable.
I'm not very good at the end of MATLAB, but assuming you can embed a web browser control, you should be able to run scripts.
At the lowest level, the IE web browser implements the IWebBrowser2 interface. This interface provides a Document property that returns the IHTMLDocument2 interface. Call IHTMLDocument2 :: parentWindow to get the IHTMLWindow2 interface.
IHTMLWindow2, , . script IHTMLWindow2:: execScript. , JavaScript IHTMLWindow2 IDispatch: , .
Delphi, execScript: http://www.delphidabbler.com/articles?article=21
.NET Framework, IDispatch (. ): http://www.west-wind.com/weblog/posts/2008/Sep/27/Calling-JavaScript-functions-in-the-Web-Browser-Control
, :
myWebBrowser.Document.parentWindow.MyJavaScriptFunction()
:
myWebBrowser.Document.parentWindow.execScript( "MyJavaScriptFunction();", "JavaScript" )