Thanks for the answer @carson.zoom!
As I mentioned couple posts earlier I tried with real user ID, but it didn’t help.
But I finally figured it out by deleting line by line from the sample code.
The ZoomSDKError_WrongUsage is returned if there’s no ZoomSDKMeetingServiceDelegate.
Connecting the delegate with onMeetingStatusChange, onWaitMeetingSessionKey etc solved this and other problems.