If you get a phone call from Multiplan asking you to lower your fee with an insurance company in order to get "expedited payment", turn them down. This happened to me and to a colleague of mine. First your insurance company doesn't pay you for sessions that you did. Then Multiplan calls you and says that if you lower your fee it will help your client. They wanted me to lower my fee $30. After intensive questioning, the agent told me that it would lower the client's copay by $5. Guess who gets the other $25? That's right! It's the insurance company. Given that the companies make massive profits and the executives get millions in bonuses, I'm not willing to further subsidize them. And neither should you.
And what's with withholding pay and offering "expedited payment." WTF?