They need to get rid of the snapping turtle they will kill, bite of legs and feet of waterfowl. I suggested warm water because it seems to help them relax and possibly lay an egg if there's one stuck.
If an egg has busted inside then she is at risk of infection and would need medical help. best thing to do would be to remove her from the rest for a few days so she can be observed enough to actually know what maybe going on. If you can pick up this duck she really needs to be gone over checked for wounds even. under all the down at skin level.
[/quote I'm guilty of brief reading you are right warm water because of the broke egg to help relax. I was thinking for general swimming.