Enabling webhooks for specific non-master accounts

I have set up a webhook only app on a zoom admin account with many non-admin child accounts under it. The docs say this should get me notifications for every child account when a zoom meetings ends but I am only receiving them from the admin account I set it up under.

I need to set this up to only receive notifications from a specific account. Another forum says you can do what I have and then filter with logic in the code that processes the payload but that won’t work if I am not receiving all accounts notifs.

The child account does not seem to have permission to create its own webhook-only apps (though it can create all the other app types) and I don’t know how to give it permission.