At the end, they have Gus's bracelet. They can finally get in to areas they couldn't before. Aurora even suggests waking up more crew to help with the falling-apart ship, but there was no time. After they fixed the ship though, there was time. There probably were medical personnel who could help with the going-back-to-sleep thing, beyond what they had available to them outside of the command ring. Maybe they were worried there would be no solution and it was immoral to wake up anyone else, but the crew work for the Homestead company. They would have had more of a duty to deal with the consequences of ship malfunctions than the passengers do.

I also can't believe there was no way for them not to put someone to sleep in the crew section. Unless we're supposed to believe the ship was launched with everyone asleep. I imagine the crew started the flight, set up autopilot, then had ways to go into hibernation. If the ship can take off, they can probably land, but the ship crew needs to wake up to arrive at the planet, so probably they needed to be operating at take-off as well.