What is the policy if a pax is a no show on an award itinerary?

I have 3 elites in my party-each of us bringing a non elite into E+.One of the elites may not make the trip-if I cancel I assume the computer will bounce their companion into E-.I am considering checking everyone in and leaving one as a no show.
Does anyone have any ideas if this occurs?Redeposit of miles,fees,penalties?