Again, don't ask me how NM Gopal Menon won his Blaze debut. The game is a fairly logical Tarrasch French: Black broke White's attack by sacrificing the Exchange, and White gave the Exchange back at an appropriate time, and it seemed that Black was OK.
I suspect that Black got a little overexcited about having a passed center pawn on the 5th rank (in queen endings, having the pawn closest to the queening square is often more important than having more pawns), and match considerations may have made him overreach. Black's king had no pawn shelter: getting mated is not a big worry in this ending, but being forced to exchange queens into a lost pawn ending is a concern. Bringing the king from h1 to e2 worked out very well for Gopal!