This link shows a 2010 Camaro being tested and it has a tow-hitch installed in the back (scroll down to the 5th photo):
http://www.camaro5.com/forums/showthread.php?t=3616
Here is the bike carrier that attaches to any tow-hitch:
http://www.discountramps.com/hitch-bike-carrier.htm
This to me is the simplest solution. I would NOT apply forces on your trunk lid or bumper.
If they don't sell the toe-hitch assembly for a Camaro, I am sure they will soon or you could work with a fabrication shop to make one, or to adapt the one from a mustang to work.