I don't have an answer, but a couple of comments:
- It's not clear, at least to me, what the expected/observed behaviour you're describing is. Some further details/screenshots might help
- Is the problem seen with the joinMeetingUrl, inviteMeetingUrl, or both?
- The CreateMeeting request doesn't have any attendees shown - what is the expected login scenario if you try to join using one of the GetjoinUrlMeeting URLs as soneone other than the host that created the meeting?
- As I can foresee site/org configs around security/user account, etc. being involved, I would highly suggest opening a ticket with the Webex dev support folks (email/portal) as they will likely want to dig into your site settings, trace logs, etc.: https://developer.webex.com/support