Let's see if @New duck mommy 2021 can give any more advice on the prolapse.
she also has a drake with angel wing and maybe able to shed some light on it too
That was in the works for 24 hrs so maybe try keeping her in a quiet place semi dark to prevent another egg from developing. Did laying make the prolapse worse?
Mine will lay their eggs in their pool so The tub may not matter. Sounds like her tummy is upset probably because she hasn't eaten. Have you tried enticing her with warm soupy feed? sometimes they will eat their feed soupy when feeling bad. You could try adding a probiotic but Most likely what...
The best you can do is keep putting it back inside do you have honey or KY jelly both will help keep it lubed until it stays in. I'd place her in a darkened room with food and water to maybe keep her from laying until it stays in laying an egg is just going to keep making it pop out.
I wouldn't...