I think JCL is right. You're basically asking for unlimited warranty. Is your car CPO or do you have any extended warranty coverage?

I posted the most common problem with the leak you described and evidently that didn't happen in your case. Since you have a 2003 I don't think you have the moonroof, which had more issues, but rather the standard sunroof. That being the case it is possible that the hose was changed before and wasn't done right or that it might have even shrunk over time (I've seen that happen to trim extensively).

No one is going to give you grief about this, I think we all feel your pain, particularly with the final repair cost. Keep in mind you're not the first person to have something crap out on their car that itself costs a few bucks in parts but hundreds in labor, and you certainly won't be the last.