The unnatural events that costed the life of the only doctor on Atkinson's team took first priority the moment Luna was given the medicine even though her condition showed no improvement. There was nothing they could do for Luna other than wait and the same applied to their mission now that they had fixed communications and received confirmation that the ship was on its way to pick them up.
The problem with that was that the ship was supposed to take a few days to arrive and in the mean time their lives would be in danger. There was also the the possibility that they might be contaminated with something that could put the lives of everyone on board the ship in danger by bringing whatever killed Evans along with them.