MessageLabs mail flow rule

Hi,

Where in MessageLabs would a person find the settings to:

* Ignore an email domains DNS MX records

* Send directly to another destination such as Office 365 for a specific domain

Now, before everyone goes off their nu...I don't actually want to do this. I'm not crazy, but I need to know where in MessageLabs I would do this so I can tell a 3rd party partner (that is crazy) where to remove this setting (which they refuse to acknowledge they have configured).

Thank you.