Managed to get the Omega2+ to talk to the WS2812B LEDs directly via Arduino Dock 2.
(I will edit the OP above to describe how... tomorrow zzzzzz)
One thing I've found however is the "OmegaArduinoDock / neopixel" python library pixel buffer seems to have a hard limit of 255 LED's !? 256 or more = fail.
e.g. npixel = neopixel.OnionNeopixel(6, 255)