I was looking at technological viability.
Even 10,000 people is just too few to fill the niches needed to keep a technological culture alive.
No doubt they would have some difficulty preserving their entire heritage, but you discount Kryptonian AI advancement. For example one of the more interesting threats to Superman is the Eradicator, a device whose sole purpose it is to preserve Kryptonian racial purity and culture.
It has immense powers and the capability on it’s own to recreate Krypton which it has tried to do with Earth, turning our sun into a red dwarf terra(or rather krypto)forming the surface and repopulating the planet using Superman as a template.
So obviously if you have access to AI of this scope that actually can teach or imprint every aspect of the culture on the individual it becomes rather difficult to loose essential information. Given that these people were colonists they should have been amply supplied with the resources and skill sets they needed.
And L&C:s Kryptonians are telepaths besides.
Of course it’s up to you but from a practical point of view I see no reason why they couldn’t prosper on a small population base, then again Ching indicates that their living conditions are harsh, even compared to human standards.
