From Theodore's observations, the people referred to by Cassian had already left the mall area; it seemed they thought that Cassian and the others were dead because the zombies had filled the mall.
Since the zombies had already entered the mall, there were only a few outside, at least not as many as when they had just arrived.
With such a situation, Theodore thought it would be easy for them to return to their truck. Especially with the help that Cassian and his group would provide, which increased the chances of them getting out of there with all the iron and metal they found.
"Should we break it down now?" Roderick spoke from behind Theodore.
"Are Cassian and his group done with all the iron and metal on the first floor?" While speaking, Theodore also turned to Roderick.
"It'll be done soon. We can do it now," Roderick said, eager to leave this mall.
"Well, if you say so," Theodore replied, nodding slowly.