Someone just needs to contact the program and ask. As far as I can see it is a traffic leak. That is not how ccbill cascading works. Go and do a test with a card that will get denied, but has the right info on it. If its cascading it will auto hand off like this.
This is from one of our sites with cascading.
I tried the same card that I used there on his site, and it just gives a pre auth fail. And asks you to make sure the info was entered correctly.
If its anything but a traffic leak Ill be pretty surprised.
The only other thing is if there is an alternative tour for the affiliates, or their links cause it to goto a diff join page.