I had the same thing on my 2009 ml63. The more I tried to stretch, glue, and futz with it the worse it got. Finally, I bought a used dash on eBay for 500 bucks. It took a weekend to remove the old dash and install the new one. It looks perfect now. I should have just done that from the get go. I make sure now to put up a sun screen and crack the windows because the hot summers will shrink and lift the leather. Good luck.