It’s well known that cassowaries can be dangerous, and indeed together with ostriches [UPDATE: and chickens] they are the only birds known to have definitely killed humans*.
https://blogs.scientificamerican.com/tetrapod-zoology/how-dangerous-are-cassowaries-really/
death by chickens?
After reading the above article and your article I’d say that falling down around these dinosaurs is a big mistake.