I don’t think it’s bugged. Insta-kill mechanic do not count as damage according to this:
I do also curious why they do not want those insta-kill mechanics to count to our score. It’s one of mechanics in the game and some of them (like deathmark, devour, assassinate, bulls-eye) is really relying heavily on RNG. I mean, it’s not even guarantee you a win if you use those mechanics.
Brown day in general tend to score low compare to other color though. There are couple team than can do very good (9.5k+) for brown day but they’re very risky to play, especially in current meta where you can’t make any mistake or you’ll get punished really hard. But again, high risk high rewards.