Just to throw another spanner in the works, I've got a 6'1 that has creases just like that in 3 different places along the board, its been like that for 2 years. The thing is beat to shit and I still use it at a couple of slabby brims-ness like reefs to avoid breaking boards I care about. Depending on how much you paid, and how attached you are to the board I'd be tempted just to ride it until it snaps then throw it away, it might last longer than you think. Its all a lottery anyway, I broke a new board the 3rd time I surfed it in 3ft waves, then I've had a creased board last years in much heavier waves. So much luck involved..
Maybe a little bit of re-glassing at the rail if its obviously damaged there.
I fixed a creased board myself and was never really happy with it afterwards, just didn't go as well as it used to, hard to put finger on what was wrong with it, probably flex related/board was twisted a bit or something. But it was my first go at fixing a creased board, a pro job and you might never tell the difference.