Yes, MC supports multiple outputs, but that would be for non-synced playback in multiple zones, not as a substitute for a multi-channel dac.
You will not succeed in sync'ing two dacs for your use, unless you have them both synced to the same master clock. Which usually is not possible with consumer electronics, but more common for pro studio equipment (e.g. Lynx).
I would recommend searching MC20 and MC21 forums, there are at least one comprehensive discussion on this topic.