How to identify Ole object Interface?

It's a bit difficult to explain my exact scenario, but I will try:

I'm inspecting a DOM interface that was created via late binding, and at some point selecting a range which returns an interfaced OleVariant Element (this I know for sure).

I was expecting an IHTMLElement2 but it is not (I get an exception that the object does not have a tagName property). Which made me later suspect (not tested yet) its a Node element (which has nodeName property) - but I don't want to guess, and ask:

if Supports(IDispatch(v), IWhatEver1)... else if Supports(IDispatch(v), IWhatEver2)...

I don't know which interface it supports. how do I know the interface name/guid from an OleVariant interface object?

The problem is not only specific to DOM, if for example, I have an OleVariant that was created via:

SomeObject := CreateOleObject('WinHttp.WinHttpRequest.5.1'); 
or
SomeObject := CreateOleObject('Msxml.ServerXMLHTTP'); 
or
SomeObject := CreateOleObject('Msxml.XMLHTTP'); 
etc...

v := SomeObject;

How do I later know which IDispatch is behind v?

I hope the question is clear.

Seems like IE11 changed its behavior when using FEATURE_BROWSER_EMULATION = 8000 for my application -> when you use TWebBrowser in design mode and select a range vElement (the Element in the selected Range) returns as JScriptTypeInfo... I don't know why, and I don't know still how to deal with this b.s, but at least I know which Interface I have!

Here is the code I used to examine the Element:

if SysUtils.Supports(IUnknown(vElement), IDispatch, LDispatch) then
  begin
    debug('vElement Supports IDispatch');
    if LDispatch.GetTypeInfo(0, 0, ti) = S_OK then
      if ti.GetDocumentation(MEMBERID_NIL, @pbstrName, @pbstrDocString, nil, nil) = S_OK then
        debug(pbstrName + ';' + pbstrDocString); // <- JScriptTypeInfo;JScript TypeInfo
  end;