Ori, you were supplied with the website and the affiliate ID why not start with going to the site in question and snooping around ???? There are links at the bottom of the doorway page that will lead you to plenty of evidence!
http://gambling.dolev-yomel.com/newdirectory/index.asp
Look at the bottom of that page 51+ pages of content; read some of the content which clearly appears to be from other sites.
Does cpays have a policy regarding the use of other affiliates content scraping stealing or use by other means without persmission? If so please point it out in your terms and conditions so that we can see it. If you do not currently have anything in your terms why not?