On most of the CPA networks you can create your own custom lockers. You also can change most of the settings for these networks. Most of the time, you can change the redirect after they completed an offer.
Network 1 = A
Network 2 = B
You can add an redirect URL from A to B. So the people will completed already an survey, will get another one. Based on my own experience, 5 – 15% will do it again. That will give you some extra free leads.