What is limited flight? going up nice but coming down hard!! Probably its just mildly flightless like some birds today who have limited flight. Yes there were birds at these times along with theropods. I think flightless birds were more likely caught by the actions of the early days of the flood. fossilizing them is no small matter. now just imagine them with more atrophied wings, bigger, teeth, and you have a theropod.
why not?