Now, with the help of the Zooms-developersupport, I can give the answer:
1.) Register the potential users as API-users:
Powershell:
New-ZoomUser -Action custCreate -Email “$mail” -Type 1 -FirstName “$vname” -LastName “$nname”
The custCreate is the important part.
2.) Retrieve the ZAK-Token:
$d=Invoke-RestMethod -Uri “https://api.zoom.us/v2/users/$mail/token?ttl=3600&type=zak” -Headers @{Authorization = “Bearer $securitytoken”} -Method Get
3.) With this Token, set up the invitation link like:
https://zoom.us/j/9…?pwd=U…9&zak=e…k
e…k is the ZAK-token I retrieved.
Hope this help
Bye
Thomas
And wonderful, the registered user is in the meeting.
The only really imortant thing is: You have to register all potential users as type custCreate / Api.
I hope this helps.