Currently, we do not have a specific flow to trigger the “Create Organization” action. You can use logs to verify if an organization has been created or not.
Type should be - API Operation
Description - Create an Organization
details.name - Organization name
For your question, the Auth0 team needs to answer if they have any other options.
The code shared is executed on post user registration and not when an organization has been created.
As @vigneshSivasamy has mentioned, your best bet is going to be utilizing logs. In particular you will probably want to look into Log Streams and using a webhook.