I will post back with the solution for posterity sake if I get anywhere with izotope support.  Anyone know how to route midi track to nectar for the harmony midi control in Cakwalk Sonar Platinum?  It is supposed to show up as a midi target like a VSTI on the midi output drop down.  It does not. 

Google helped.  In sonar if you open isotope nectar 2 from the effects bin of the audio track you are working with, there is a gray bar along the top of the nectar plugin window, it has a little drop down that says VST3.  On that drop down there is an "enable midi input" option. 
 
That option must be checked as well as the midi control button inside the nectar 2 harmony module in the overview tab of the plugin.  
 
This is probably a basic plugin operation that I have not needed to know til now. 

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Almost as fine as bassy daddyu 

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