Yes, as far as I can tell. The manual doesn't give a layout for stereo subs being fed from the processor, but I am using the dedicated side/sub out on the 568 (comms from the 511) & daisy-chaining one to another.
Could the fact that in mconfig/sizes they are set to 30, not max be a problem?

568.2mm, DSP6000, DSP5200HC, DSP33 rears, HD621, LG G3, Sony UBPX800-M2, F80.