Sorry for the long break. I had to wait for response from the admin. However, the settings should be fine. My colleague is able to log in/authentificate using my computer and I can log in with my account in anything except NoMachine. The administrator also said, that I don’t need special permission for NoMachine.
I don’t know the version of the organization’s server. Does it make a difference? I tried the version offered from the organization (5) and the last version of 6. Both cases doesn’t work. They also offered download on there side for Windows and Linux (no version mentioned).