Here's what I would do. I would beg/borrow a fish net and catch Clarice. Put her in the dog crate on the front porch for a week while the new birds get used to the pen. If Svetlana is too hard on them, put her with Clarice. Once the new birds are used to their pen, they won't act like victims when Clarice and Svetlana show back up. Before you reintroduce everyone, lean some large pieces of plywood against the sides of the pen, so they have plenty of places to hid. Maybe a cardboard box or two sitting in the middle of the pen. Out of sight, out of mind in chicken land. Put extra bowls of water and food here and there so no one has to venture out too far to drink and eat. They should be able to work it out.