Sure, there's no need to divulge your ultimate secret weaponry while we're still at war.
I suppose if you had Virtue on a communion master, then since the Returning effect is triggered like Charge Body on copper plate, then the slaves could end up with Ritual of Returning set. But even your Castellan has Ritual of Returning, and he couldn't have been a communion slave. So you'll have to fill me in on all the gory details after Mictlan has finally finished conquering the world.
