Same situation here with my 2005 base coupe. The headliner started peeling and got worse. Must also be the Texas heat! The guy charged me 100 dollars here in San Antonio. He was recomended by my body shop and had been doing headliners for 40 years. He showed me the old material and the foam.... couldn't believe how bad it was for such a new car. He said they probably used bad glue but more importantly did not wrap the headliner around the edges properly. He felt they should have wrapped it around and sealed it up better. Once moisture gets in, it is all over.

900 dollars at a dealer for the same old junky headliner that will probably peel again? Forget it! I bet your new headliner will stay on longer than we will live on this planet!