Yeah...finally we end up by drilling a hole in the inner fender. The PDR guy said that thru the tail light was too far from the ding to have enough leverage.
Very satisfied with the result. It is back at 99 %
Impossible to see by someone who dont know where exactly the ding was.
It was his first Boxster. He said the metal sheet is thick like hell and kind of difficult to work with. But end up pretty well.
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Before
After
Again thanks all for your input !