A couple of things here. First...Kem EL is recreated in the phantom Zone by the Eradicator (who just happens to be quite proficient at T-VO.)
Kem explains that the Eradicator can turn Earth into the new Krypton by evolving humans and even the planet itself.
Lastly, Superman is sent through time through the Eradicators machinations and meets his own parents right before krypton explodes.