The impact has delaminated the RPC, so you'd have to sand through the layers until you got back to the first attached layer, and that may be the wood.
I'd give sanding back a go, as you've got nothing to loose. If you hit the wood and start taking off the stain, then it's still not the end of the world as it is solid black and not a fade transition area, so it should re-stain OK. If it doesn't look right, then you can still do the full strip back.
Reply With Quote