To be clear, it does not matter whether you play DSD from a USB stick or send it via RAAT from Roon. The CXN converts any DSD input to PCM, even from the USB stick. The CXN cannot, as in never, no matter the input source, play native DSD. It will always convert the incoming DSD to PCM first.
This is because the DAC chip used in the device cannot play a DSD signal. It can only do PCM.