It's pretty common for email administrators to set up custom rules within their email filtering software so that emails which match both of these conditions will be accepted (and all others rejected). There is very little likelihood of someone sending from Newsletter Tool's servers and using your domain in the Friendly From address, so that's generally an acceptable solution for email admins.
- The email contains one of the Newsletter Tool's sending domains within the 'Return-Path' address (bounce tracking)
- Campaign Manager uses one of these domains in the Return-path: cmail1.com through cmail20.com
- Whitelist Newsletter Tool's domains (cmail1.com through cmail20.com), as any email sent from the Newsletter Tool will contain these domains in the return path.
- The email contains your domain in the 'Friendly From' address
- In that rule, they'd also require the return-path above and that the email was coming e.g. from a @YOURDOMAIN.com FROM email-address.