...titled "Some Info for Providers" has information about the White list. Click the link, scrol to the bottom, read the part titled "Whitelisting", click the link "Whitelist FAQ".  

 
Note the Whitelist FAQ's are written from the client point of view.

 
...and the answer to the question is Yes you can Whitelist your clients. You have the free limited Provider VIP which gives you that ability.

I'm a provider, how do I submit a referral?

 
Go to "Reviews" and click "Search White List" Type either the user name or e-mail address and click "Submit." When the user's White List appears, click on the button that says "Submit referral." It's that easy.

At the bottom of any page, you'll find "Site Map."  It's makes it easy to maneuver around TER.