We're now taken back in time to Day 6: the day everything went bad.
Although the crew (that's Vogel, Martinez, Johanssen, and Commander Lewis) knew that there was a storm brewing, they had no idea how crazy that storm would get.
The dust storm hits and the crew hides. After receiving the order to abort mission, the crew must now run to the Hab in pairs while being pounded by the "roaring wind" (12.55).
You know what happens next: Mark gets impaled, stranded, left alone on Mars, etc. This time, however, we see it from the crew's perspective. We watch as the crew agonizes over the decision, with Commander Lewis withholding judgment until the last possible moment.
Fast-forward to the present day and float on over to Hermes, where the five remaining crewmates wait for their "daily dump" of "e-mail videos from home" (12.192). As you might've guessed, this particular load contains some very important news—Mark is alive.
The crew celebrates, but the moment is sullied by a dark mood. Commander Lewis, in particular, seems absolutely guilt-ridden about leaving Mark behind. Fair enough.