Why didn't Kazuya use his freezing ability against Chiffon?
First of all, Kazuya doesn't know how to control his powers. This can be seen every time he uses them. It is always in the last second and only if somebody is in danger, especially Bridgette.

In this fight, he is unable to use it, because he does not want to hurt Chiffon. Also he sees that Rana and Bridgette have no chance of winning any way. Rana's arms were ripped off in a second and after she transformed and beat up Chiffon, Chiffon just stands up as if nothing happened.


   Also, Kazuya's powers are needed a bit later and he tends to overexert himself. So it would be impossible to solve the problems which arise later.