I actually attended the game and I highly doubt there was 10k for kick off. It did fill out quite a bit after kick off though.
I'm not saying that the Raiders padded the numbers for this game in particular, there's no way for us to know that alone prove or disprove that, but if you guys honestly believe that none of the NRL clubs pad their numbers out from time to time then you're unbelievably naive.
With the exception of teams that are more or less selling out every game (and thus have no need to pad their numbers), every sport's team, and event in general, pads their numbers out in one way or another at least some of the time. Whether it be dodgy counting methods, including all tickets sold in the attendance figure, papering, etc, etc, or some mix of all of the above, it's a ubiquitous part of the business that happens regularly in all sports.