Add registrant to a webinar - jquery

We need implement in our website a button to allow the logged users to register into a webinar

I have made a test page implementing the javascript code provided in this page

But I get this warning message in the console (firefox): Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at (Reason: CORS header ‘Access-Control-Allow-Origin’ missing).

We cannot change anything in our server and we cannot use server calls to zoom api, we have to use javascript code jquery (client side)

Please, could you tell me if is possible implement this functionality and what are the steps that we have to do?

Many thanks in advance

Duplicate, please see - Add registrant to a webinar.