In #3 of the sutta:
Then those beings started to eat the earth’s nectar, breaking it into lumps.
But when they did this
their luminosity vanished.
And with the vanishing of their luminosity the moon and sun appeared,
stars and constellations appeared,
days and nights were distinguished,
and so were months and fortnights,
and years and seasons.
So far had the world evolved once more.
What I understand from this is that those beings were bright enough that the moon, sun and stars were not visible to them, not that they didn’t exist. While I am not sure what type of “luminosity” is being referred to here, these are beings who descended from the abhassara realm, which is referred to as the realm of “streaming radiance”.
