I had an Oldsmobile that had a bulge that remained intact for a long time, but it went out at turnpike speeds in Oklahoma. You never know when the sidewall will let go.
That damage looks superficial on the pic adn can only be a bit of scuffing. I think the tire might be fine. You can have them take it off and check the sidewall on the inside for any damage. But then again sinc eit is Dunlops it might be a good time to get a set of nice tires