Discarded.
Allowed to die. If the theory that the dim ones have damaged DNA is correct the dim ones wouldn't survive the pregnancy anyway.
What would you do with the doomed eggs?
There's the germ of a SF story here. The dim eggs are frozen simply because we can't bear to kill them or even allow them to finish the process of dying.
Some of these eggs are perfectly healthy but had the second brightest glow in their cohort, most are genetically damaged to one degree or another.
I can see where a law would be passed requiring the runners ups to be cryofrozen.
Imagine a future where the human race has survived a biological warfare event that has permanently damaged the entire species genome.
Fertilized eggs, even somewhat defective eggs, from before the war are a big improvement over what we have doing it the old-fashioned way.
Still a lottery, prospective parents have no way of knowing if a given egg is completely healthy, mildly handicapped, or even anything about the ethnic background. They do know, no matter what, the child will be healthier than any monster they could make on their own if it survived and few do.
What would a society look like where every child was effectively adopted, and few children looked like their parents, and half the kids were physically or mentally handicapped, but one where the species could survive where it otherwise wouldn't?
It might be that the eggs that fluoresce most brightly are actually the less viable ones since their cell membranes are obviously more leaky (more calcium channels reacted). Ethics aside, I’m not convinced they know whether this is actually a reliable measure of cell viability.