Also do be sure that the USBa-to-micro USB connecting between the RasPi and AUC is a data cable and not just a charger/power cable like typically found with phones/tablets... Been there, done that - they are wired with all 4 pins as power and don't work.
And the winner is.....
As soon as you mentioned the power vs data I knew what I had done. I had grabbed the charging cable for a hand held trouble light I have in my shop.
Hashing out on all 4 miners now - thanks!!!
PS: Also had a bad network patch cable when I set up the controller. Fortunately noticed right off the bat because the light flickered but still - two bad cables on the same project - who would have thought....