If $ is already defined before dnn.js runs, dnn should not change how $ is defined (this has been there for a while).  All dnn requires is that $ still does document.getElementById and returns a ref (it can do any other things as well).  $get from the MSAJAX framework is the new recommended alternative.  For DNN5, nearly all (if not all), refs to $() have been removed.  It is only kept in dnn for backwards compat.

Hope this helps.

Good question. Anyone have an anwer?

I am loading jQuery in the Head, and dnn.j is loading in the body, but is still causing $ conflicts.

Error: $(document).ready is not a function