Use a good magnifying glass, something like 20x to look at both the connector on the board and the tip of the cable.
1st, the connector: make sure nothing is damaged there. It could be that the flap is dislodged, or the prongs bent, etc. May be that's why you were having a hard time re-seating the cable. In that case, changing the keyboard will not solve it.
2nd, look at the tip of the cable. May be if you're lucky the golden tracks have been displaced but not broken, and you could position them back in place using a needle. I had this before and this method worked for me.
3rd, look at where the scratches are, to see if you ruptured any of the tracks. Let us know if that's the case and post a picture to see if repairable.
Good patience and good luck. Don't rush it unless you want to shell out $30 for a keyboard and 1 hour to replace the keyboard (which is held in place by 52 tiny screws, underneath the motherboard. Everything must go before you can change it).