Oh wow Slick that is a tuffy! I would be very worried too and I'm not sure what I would do. If you go with the crate option is there a corner in the bedroom maybe where the workman won't spend as much time in. I think I would put the two crate doors facing each other so they can see each other. They may not want to spend time together but there surely would be some comfort for them to see each other. Maybe you should cover the crates too so they can't see all the strangers coming and going.
I would be totally freaked out by this too but you know how they never cease to amaze us and will probably deal with it better than you. Keep us posted on what you decide to do.