Spayed Bunny and her bonded friends

Hi all,
i have a bonded trio of girls, one of which was spayed yesterday. They share a playhouse in the garden with access to the rest of the garden a couple hours a day for exercise. My vet told me to keep my spayed girl indoors until her check up on Monday, and shes not allowed to sit on hay, straw or shavings. I ended up covering my downstairs loo in some towels put some bowls of food and water made a makeshift hay box out of a cardboard cat food box and left her pet carrier in for her. Im very worried about her becoming un-bonded with the other two, i have brought them in this morning and they are all together at the moment in the toilet, ive left the door open so they can go in the hallway as well.
im just wondering what other people in my position have done so their rabbits don't lose their bond. i don't know if i should keep them together until monday?. Im assuming litterboxes are not a good idea for the spayed rabbit? I have done some research and keep reading conflicting advice, one site said the best thing for her would be to put her straight back in her home with her bonded mate/mates as this will comfort her and help her recover quickly, while others said to keep her indoors for the first few days.
I would be so grateful for any advice!
thanks in advance

Could you divide the playhouse up so she can still be outside with the others but safe in case they attack her? If she were living with a male rabbit I would say keep them together, but it might be slightly different as they are all girls. I hope you find a suitable solution.