Large, Flightless Dinosaur-Like Birds

I have already written about sightings of large bipedal creatures in North and South America which resemble theropod dinosaurs. I concluded that those sightings are probably of large, unknown bipedal lizards. However, there are also some reports which describe features that appear to be characteristic of theropod dinosaurs. For example, there are some sighting reports which state that the animals had three toes, and appeared to be covered with fur-like structures on their bodies. Both of these characteristics are not really compatible with the lizard identity. 

Therefore, I have come up with a new hypothesis to explain these odd sightings. I feel that there is a species of large flightless bird living in the Americas which has evolved tooth-like serrations in its beak and a long, bony tail. This may sound unlikely, but in reality, it isn't. There are many birds alive today with tooth-like structures in their beaks; one example is the merganser. And there are already many birds which have claws on their wings, such as the ostrich. And finally, there was an extinct flightless bird called Sylviornis which had long, bony tails, just like their non-avian theropod relatives did.

These birds are probably around 5 feet tall and 9 feet long. They have a beak with tooth-like structures in it, which they use to help catch their prey. They are omnivorous, feeding on nuts, seeds, and insects, and occasionally taking larger prey, too. They most likely belong to the order Galliformes, which includes chicken and turkeys, as well as Sylviornis. In fact, they might actually be birds in the same family as Sylviornis that evolved tooth-like structures in their beaks, wing claws, and even longer tails. 

So, this is my hypothesis. I would appreciate any feedback or constructive critiques of it. Cheers!