First off, if a BO tried to move me from one stall to another depending on his mood, I'd be moving. QUICK! I won't tolerate that kind of nonsense, period.
To help your stall. If you can't get it open to sun and air, then there are a couple of products that will help. Sweet PDZ is one and Stall Dry is another. If you can't find either one, if you can take a bunch of the pelleted horse bedding and put it down to mix in with the mud, it will absorb a lot of the water and help dry things out.
I second moving the horse to dry land, otherwise you're liable to have some hoof/foot/lower leg issues from the wet.