There was still some time until the national competition, and considering the rewards that he received, Kain figures it was time to finally evolve Eve and the Vespirae.
He knew that the royal jelly was a necessary evolutionary material, and that a skill used to permanently change the attribute of the royal jelly must be acquired. This was the most challenging requirement, and probably why there had only been one historical instance of a Vespirae evolving, especially since this evolutionary condition was completely unknown to everyone except for Kain.
Additionally, he received an unknown life attribute crystal from the relic that was probably another suitable evolutionary material—so Kain had everything that he needed.
However, to ensure that the evolution would be successful, Kain of course also ran a Simulation using the System.
