Most of them stayed quiet, they'd done so well for days. A few gave up and wandered out, probably making it to Claire at the nightclub or wherever they deemed to be safer. Once they left the Hall he didn't worry. They either made it or they didn't, Owen could only help those who wanted, and check in with Claire to make sure she was alright in her own 'safe' zone.
The Tyrannosaurus was close enough to shake the walls that looked like they'd crumble on a sneeze, if only because Owen knew just how powerful the Queen of all dinosaurs could truly be. From first hand experience.
When it was unbearably quiet a few stragglers wanted to check outside. Surely it meant the beast was gone, but no, there had been no trail of footsteps to indicate as such, only the silence. She was still looking and smelling for movement. They'd all been huddled in one place too long. No amount of sealing the cracks, doors, and windows could contain the heavy scent of humans bunkered down, much less the ones who moved to the windows, against Owen's persistent flailing.
At the first sign of movement the Rex roared to her prey, flinging her body head first, all that weight and momentum into the Town Hall. The people were easy pickings with no roof, running about the Square like ants.
"Stay hidden! Don't move!" Owen told them, in vain, keeping to the walls and wherever was most dark.