[JR 1]

I had the same problem with mine as soon as I bought it, and I actually had 2 separate leaks. I work for GM and I talked to a tech at the proving grounds who worked in Camaro convertible development and he said 9 times out of 10 it is the drain hose not being installed properly. That was one of my leaks. I have a 2012 and it only has two drain tubes at the front that dump right into the 'wet' area of the quarter panel. Starting later in the 2012 model year GM added two additional drain tube which are routed through the trunk. The early design will keep your car dry if the tubes are fully inserted. If not fully inserted the water will end up in the rear foot wells. The tubes are very easy to check, and I'll try to post some pics.

My second leak was in the trunk area. There was not enough body sealer between two panels and resulted in a pretty good stream of water coming in under the tail lamp that would fill up the spare tire tub. This kind of leak is not so common.

Bottom line, if your foot wells are wet and the dealer tells you it is something other than the drain tube I would be suspicious that they didn't find the real problem.