I don't really see how, as there is no debugger, per se, in LabVIEW in the sense that that function expects.
What I meant is, the LabVIEW application should keep posting messages using the OutputDebugString() API so that some debugger program like Dbwin32 can capture the messages and display it. If that can be implemented, it will serve as a mechanism to observe what the LabVIEW application is doing now and also it will behave like a probe so that we can utilize it as a debugging tool.
Well, I suppose you can try calling it using the Call Library Function Node. The prototype for it is pretty simple - it just has a single string input.