a question regarding the couples + Rosenthal

The team  that we see in Alien Covenant where kept separate from the other Colonists because these team was the initial specialists required for the mission once they reached their destination.

And not all of them are couples, Rosenthal, Ankor, Ledwood and Cole were part of the 6 Member Security team of which only Lope and Hallett were a couple who would be brought out together.

The other 4 do have Partners who are with the remaining colonists in the other Cryo-Pods... so Provided they did not perish in the initial lose of 47 Colonists due to the Neutrino Burst Storm then the Partners of Rosenthal, Ankor, Ledwood and Cole would be in cryo-sleep unaware of the fate of their loved ones.

Never mind the True Horror that is now aboard their ship.

*note maybe not everyone on board is a couple, just the majority are, and some of the crew in Alien Covenant have no wedding rings but this could mean they merely are not Married.