If I think I have a broody I give them golf balls or fake eggs for at least a week till I know for sure they are committed before I put anything under them I want to hatch.
Personally I'd pull the 3 that are completely dry, they are also probably the most active. At 48 hours pip and no progress assistance is needed. I'd start the process of removing some shell slowly keep the membrane moist. Also check to see if the chick is still alive.
I have two coops. They pick where they like to sleep between the two. I don't have a run so I have no advice for that. Once in awhile someone will mixed it up and be in the other coop but for the most part they are all older now and have there spot. I'm planning to build another coop this spring...