Timed Challenge Counters...

So yesterdays timed challenge was, "Defeat 10 Enemies With A Blaster Wielding Hero"...sounds simple enough...

Game 1, 22 eliminations, 11 kills - Registers 2
Game 2, 16 eliminations,  8 kills - Registers 1
Game 3, 21 eliminations, 13 kills - Registers 3

Game 4, 11 eliminations, 6 kills - Registers 1
Game 5, can't be bothered, broken

For an achievement based game, achieving the achievements should be achievable...surely?