Yeah, that looks like raccoon poop. They are stinky like you describe. At least the males are. They are also very strong, and even more destructive in groups. When I was younger, we had an old camper trailer that got turned into a tack and feed room. It had power and a working fridge, plus a chest freezer in there. Coons pried the door open and destroyed it. they ripped the fridge door off, tore through the feezer, tipped over 50gal drums of feed and ripped up saddles. They were caught in the act due to the noise, but if they hadn't been caught, a bear would have easily gotten the blame.
I'm very sorry for the loss of your chickens. I do agree with others that is possible some of what the coons left behind was scavenged by another predator.