The answers to all of the above are yes - though my PawPaw have not yet borne fruit, so I don't have personal experience with my flock eating them. My flock has eaten american bueatyberry for years - also a popular place for hidden nests (you've been warned).
We don't have autumn olive here, and my actual olives aren't expected to bear fruit till (maybe) this year, next year more likely (arbequinas). I thought we had cotoneaster, but what we have is too tall to be, so I won't make comment from personal experience there.
I will however, say that it has been my experience, and broadly the experience of others that, give options, a chicken will not eat to excess things likely to be short term harmful to them. There are a number of plants in my pasture which are potentially highly toxic which I continue to try to eradicate. My chickens, ducks, turkeys, goats all simply avoid them. They have better choices avalable to them.
Hope that helps some