Novice,
I think you will find that the problem lies with CASA. It is their requirement to have your permission to release your information, I assume due to Australian privacy laws. I don't believe the same requirement exists in Japan. Have you tried to advise CLARC that permission is granted and they can go ahead and seek verification from JCAB of your rating.
The application form you compete only includes a box to be ticked indicating you have given JCAB permission. Tick the box and submit the form! Worked for me a few years ago.