I don't know how long this creature has been trapped down here, but the stories of the hoarvor pit go back as far as my grandfather's grandfather. It's been down here the entire time, and they've been feeding on it.
What else could Daedric blood do to hoarvors but make them mean? And large. I doubt I'll be able to find a way back out; they nearly killed me on the way in.
At least the hoarvors will have something different to eat for a change.