Everyone pretty much covered the scenario.

You probably hit the intestines as the material there tends to be greener and slimey while the stomach matter tends to be brownish and mixed with blood. Intestines and stomach matter quickly plug holes making any sign limited at best. Especially when they lay down, the insides move around and really plug the holes. That could account for nothing in the bed.

It is dead, just your job to find it. My longest living gut/intestine shot that I've had first hand experience with has lasted nine hours.

Always go to the water. Check every source available. I'll bet dollars to donuts that is where you''l find her.

Greg