My owns a 2007 Dodge Caliber and last year we noticed it had rust spots from the inside of the paint job, the exterior is smooth and has not come thru it yet . We took it to the dealer last December and they sealed and baked it. We just noticed couple weeks ago that that the rust spots are back and are back and all over the vehicle.
You may really have to go and push hard on this issue. An '07 rusting already? Is this a beachfront car, flood car, etc.?
If rust is bleeding through I don’t see how the dealer could have simply “sealed and baked it”. That sounds like a stalling technique.
You need to make sure that all documentation is kept. Paperwork, and its trail, is an absolute must.
Sorry I can’t be of more help here but an '07 with rust issues like this kind of boggles the mind a bit.
(Guess I better email my son tonight, have him take a close look at the '07 Caliber he just bought about 6 months ago, and make sure the rust weevils are not attacking that one too.)