8. ... Qc7 leaves the RHP master games database. 8. ... d5 or b5 looks to be most successful.
9. d4 cxd4
Now left my own database too. 9. ... e5 was played, but did not have more success.
10. cxd4 Bc8d7 11. Bc1g5 Qc7a5
I found this a bit over-aggressive. After 12. Nc3, the Q has very few squares. Perhaps h6 (computer suggestion).
12. Nb1c3 Rf8e8 13. e5 Nf6g4
My computer gives White a two pawn lead in this position. The N had to get away a move earlier. Nd5 may be less bad, as the Nc3 is attacked, winning back a pawn.
14. Bg5xe7 Nc6xe7 15. Nf3h4
15. Nd2 was better, as the white N then goes to c4, attacking the Q and winning the pawn on d6
15... dxe5
?? In black's words: "ops well that was the massive mistake of this game". I have to agree. Blunders get rarer by making the move on a board, and then looking at what the other side can do. White is now a piece for a pawn up without compensation.