I\'d keep on the dealership - eventually they will reshoot the underbody molding to make it disappear. Just go up the chain of command at the dealership, if that doesn\'t prove satisfactory - then contact Toyota Corporate. That usually will light a fire under somebody to get things rolling for you. If that doesn\'t work - a call or email to the BBB will definitely get the dealerships attention. Dealerships that I\'ve dealt with were the same way - not very helpful, but a call to Corporate fixed that fairly quickly. Just a couple days downtime to reshoot the paint - rental car on my nickel on the GM and Honda, Dodge provided a rental - but the Dodge also needed an additional trip to get overspray off the wheels and molding.
I haven\'t run into any issues with any of my metallic colored cars (all my Toyotas, to date, were metallic) - but the ones that were a single color (Chevy, Dodge and Honda so far), I\'ve had paint issues but I haven\'t experienced the paint staining. I did have huge sheets of paint shed off these brand new cars or have an exceptionally large number of chips on odd places on the body (ie, not the hood or rocker panel areas). Note - this wasn\'t the case 10 years ago or so for imports, 15-20 years for domestics - as they used regular urethane or acrylic paints - i.e. hard paints.
My 1996 Camry had flawless paint, chips \"healed\" quickly and zero corrosion took place, even if I neglected the chip. Car still shines like new. My current cars - not too bad, but chips show up very quickly and there are a TON of them. There is a little surface corrosion on some deeper chips of my Corolla (didn\'t fill the chip yet, planning to reshoot the whole car with different paint).
Keep at them and good luck