Asking your local OPEL dealer is not an option for you?
Are you sure that the easytronic clutch is a wet one?
I'm sure the easytronic 3.0 module contains this reservoir, on which CS OIL is ONLY. For example, the brake fluid reservoir is DOT4.
I searched the internet for many other countries on Astrak forums, but to no avail, except in Vauxall K, UK, where a user asked the same question.On the picture above you can see the easytronic 3.0 container and the top is CS OIL ONLY.