Hi @tomaz_turk ,
No worries at all, can you please give this ago, I followed this process and was able to clarify that indeed you are correct, it is a tickbox, and this seems to work.

On your instance you can use the Canvas Live API (check out https://community.canvaslms.com/docs/DOC-14390-canvas-apis-getting-started-the-practical-ins-and-out... for details on how to do this).
I ran the CanvasLive API user create call, only including the account ID, pseudonym[unique_id], and set pseudonym[send_confirmation] to true.

When I got the confirmation email, it had the tickbox as you would expect.
Please let me know how you go replicating those steps, as, otherwise there may be a setting that we can't see that your CSM may have to enable for you.
Look forward to hearing from you.
Stuart