Email Activity access based on Contact Owner

Hi All,

There is a requirement to restrict Email Address field in Contacts based to only record owners (Team). Hence, we came up with below solution - Not before breaking our head for around a month :)

1. Create different Email address fields (e.g. "Team 1 Email address") for different teams (e.g. "Team 1")

2. Create a Field security profile and add this field ("Team 1 Email address") and relevant team ("Team 1")

3. In Contacts, display this field based on Owner (e.g. "Team 1")

4. Then, hide the OOTB Email address field from the Contacts form and update the custom field's value ("Team 1 Email address")

5. Also, made the OOTB Email address as field level secured, so that it won't seen in reports/advanced find view, etc.

After all this, an user asked a valid question that, what happens if some one else other than the Contacts record's Owner (e.g. "Team 2") tries to create an Email or Appointment activity?

Ultimately, we want to restrict only the record owner ("Team 1") to create an Email or Appointment activity.

Can you guide me how to set this security one?

Thanks,

Praveen.