Compared to the outside, the gymnasium was the safest and sanest place they could find. There was also a lot of space within, so Cain was able to get his much-needed privacy.
While the interior of the gymnasium was fairly okay, that didn't mean it was at 100 percent. Some parts of the roof had caved in, and there was debris all over the place with all the equipment and furniture scattered over the place, but compared to the pile of rubble outside, it was paradise.
Since they all had a day before they headed into the forest to search for a way to get to the main campus, they decided they would all do their own thing while waiting for Cain to make his preparations.
David and Blaze searched for survivors since there was a possibility of someone hiding out in one of the storage closets within the building to preserve their lives. They had no intentions of leaving anyone behind if they could save them.