Two things:
1. Jailbreaking voids the warranty, so they may/could just tell you your out of luck, so do NOT take it back in its jailbroken state - you need to restore it with the factory firmware and only take it to Apple if it's NOT jailbroken.
2. The picture issue with the green tint is a known issue and affects all units (it also affects other camera phones / cameras). The problem is the CFL lighting - the camera picks up the green hue from the fluorescent lights and exposes it onto the image. Really, the only workaround is to not take photos under CFL light conditions (I know this sucks, but that's the way it is). I returned mine to try another because of this issue, but the replacement has the same issue. In fact, the Genius tried some of the Apple store employees' phones and all had the same issue.