Well that sucks.
Don't be too hard on the @little-peppers. Not all lessons learned are easy ones of pleasant ones.
I'm sure whoever it was that was supposed to look the door feels really bad today. And I have no doubt that they loved the chickens and the duck just as much as you did.
All you can do is take the hit, learn from it, and move on and make sure it doesn't happen again.
Can you spring load all the doors you have, to make them stay shut tight in case someone forgets again?
You might want to look at getting some geese. They are really good at guarding a property, and very few animals will take them on.
I hope your day improves. ;-)
Geese would be no challenge for a big raccoon. They'd be helpful for most normal raccoons though, I think, especially if you had a half dozen. Geese will gang up on enemies.
They also make a bunch of noise when they feel threatened, which can be good for alerting the homeowners to trouble.
Boy do they! Not many will sleep through it, that's for sure.