got to see the G8X in person and as funny as it sounds, I think it looks better with the full vertical grilles versus a painted piece to split it into half, reason being, the grills are literally designed to flow into the raised hood lines. I don't even like them really but breaking up the big grilles just makes the top half of the kidneys look like incomplete trapezoidal shapes that don't match up to any lines on the car, or it also reminds me of when someone tries to imitate a piggy face by pushing up on the tip of their nose
I think the biggest mistake was not making the grilles vertical, but rather just making them sit a bit too tall to where the top of the grille sits above the headlights. For reference, the Alfa has a vertical grill but the proportions are far better and therefore that car makes it work. Unfortunately I don't think you can fix the issue with just a grill addition. Props for trying though.