Here's what I'm wondering, "Was the latch closed when you found your rooster missing?"
If the latched was closed, someone stole your rooster. A coon is not going to re-latch the chik-n-barn. Most people it is second nature to redo latches and doors and what not. I think it is weird how you are only missing one chicken from that chick-n-barn(unless he was in there by himself). Any footprints you don't recognise? If you redo the latch, I would go with a lock of some kind. One that requires a key, to keep both coon and human out.
You could also think about dusting the surfaces a coon would have had to stand on to undo the latch. I don't know what your hutch looks like or if a coon could do it from the ground. If you dust with flour or something footprints would show up next time the coon(or whatever else) came back to see if it could get a second meal.
Good luck catching whatever it is. Sorry to hear about your roo.
-Kim