pretty...but I probably would have just left that little dent alone. It wouldn't have affected your performance or speed. Boards are saturated with epoxy, so, it wouldn't have taken in water, either.
granted, prices are much higher in europe, but I think those people at your shop saw you coming and took advantage of you. By the time you get a couple of core shots and other dings, that little dent will look like nothing. I, at least, would have waited until more significant (non-DIY) damage and got a bundle repair deal at the shop.