What I did only once was remove the leghorn to a nesting box in another part of the run - where she had laid previously. She did lay and other hens got to lay closer to their time of choosing.
What I’m wondering/asking is if I routinely place the leghorns in a different nest box will they eventually chose that nest box voluntarily?
The leghorn in the picture intimidated the hen in the box before she laid and is now in it herself. I have seen the peck or grabbing of neck feathers to literally pull a hen out of the box. This is not always immediately followed by the leghorn laying! She may cruise the nesting area for another half an hour before laying, blocking others from using any of the boxes.