so. species swap au. Ilyukhina survives radiation sickness the longest, but ultimately, Grace wakes up alone.
Eridian!Grace is put into a semi-permenant sleep at Eridian!Stratt's orders. His crew takes turns watching him, even without fully understanding the patchy reasoning they were given for his condition. Grace's sleeping spot is near the back of the ship.
When the crew begin to fall ill, Eridian!Ilyukhina keeps her health the longest, so she moves Grace into the engine area she works in so he can be watched while others are either very sick or very busy trying to figure out the sickness. As things get more dire, it is common to sleep in the engine room since Ilyukhina is the only Eridian healthy enough to stay awake long enough overwatch a sleep cycle. Many Eridians die in the engine room. Yao is lives the third-longest, spending his last days with Ilyukhina, unable to figure out why they are sick, or why the ship is going faster than it should be. They can't tell is Grace is sick, or if he will ever wake up, but they hope for the best.
Eventually it is just Ilyukhina and Grace, with Ilyukhina desperately trying to figure out what is wrong with the ship, what killed all her friends, wondering if she and Grace will make it. She only sleeps when her body forces it and pretends Grace was watching her sleep.
When Grace finally wakes up in the Tau Ceti system, nearly the first thing he senses is Ilyukhina, close enough that she must have been watching him, but she is completely still, having long entered her last and eternal sleep. It doesn't take long to realize he is the only one left alive on the ship.
