I have owned a 2006 Suzuki Swift from new and the roof has separated from the internal cross braces and is oil canning or popping in and out. I have checked two other Swifts and they are the same. Suzuki only wants to send a report in; do you think they should investigate it and repair it?
I agree, they should take a look at your car and discuss your concerns with you. You don’t say that the oil canning is evident in any other way than by pressing down on the roof. If it’s not it’s necessarily a problem, but I would still press Suzuki for an explanation.