This is an old post, however, I feel it's important to put another option out there...with the weepy eyes and slightly protruding vent...to me it sounds like a snake got to her...I've had it happen and actually was able to resuscitate one hen that was completely limp..the snake was still coiled around her in an effort to constrict her to death..then eat. Unfortunately, after they've constricted them to death, it's only then that they figure out the hen is to large to devour...so my guess is snake constriction. I'm sorry for your loss. It's always hard to lose one, no matter how.