Could be I guess... I'd just think you'd have smelled it in the coop.
Not unless it sprayed, which it wouldn't do unless it was threatened and a chicken wouldn't threaten it...and the coop is all open...just chicken wire, mostly, so the smell wouldn't stick around unless it was sprayed.
I'm just thinking it's gotta be a coon or a skunk and I'm leaning skunk now that I know we have one in the area. I can't imagine a cat doing it and a dog couldn't get in without digging a hole under the fence...I don't think...
Wish I could put up a webcam!
But the scent is a defense mechanism. The skunk wouldn't have felt threatened.