Using Label property of Office Ribbon Control in vba

Is there a way to read/get the Label attribute of an Office 2007/2010 ribbon control in VBA? The only exposed properties appear to be Tag, ID, and Context.

I'm trying to use the getLabel and getVisible callbacks together--read the label and determine whether or not to show a control. I tried setting the Tag property in the getLabel callback, but the code won't compile as that property is read-only by then.

Any other suggestions for how to skin this cat welcome. Note that I cannot use a dynamic menu; this is under a split button, and has to stay there. Thanks in advance.

I suspect that VBA doesn't have access to customize the Ribbon UI. I do know for a fact that this can be handled with VSTO.