Plot hole: one of the alpacas says that only animals with sharp teeth could eat me, yet when I tried to eat a horse, I died.
Viewing post in Alpaca: Escape For The Butcher's Shop comments
Actually, it's game logic. "I know an old lady who swallowed a horse... (she died of course)" And so will you if you try to eat horses. Basically, it's not that you're being eaten in this case but that the animal gave you explosive indigestion.
When you have eaten everything not likely to cause upset stomach, head to the farmer up top and he'll give you a key to the gate.