Re: track down the perps!
Seems to me there 2 types of scam they could be running
1) "our website got you clicks on your ads - give us money" - which is scamming the advertisers , and would work better not showing the user
2) "We will get your ads seen - give us money" - working with the dodgy advertisers, in which case the dodgy advertisers would check wether the ads were appearing visible or not.