Why does zombie assault 3 say i only killed 20?

Ok, so as most of you know ZA3 has more cheats than. . .well its pretty bad. Anyways After I finished a match with a bunch of cheaters (I noticed right away from them spinning in circles and never dying) I thought "wow I bet I got the top score, easy" I looked at the screen I had only 20 kills, they all had over 300! I thought this might have been a cheat or glitch, execpt that this happens every other time I play now. Not only is this annoying, I'm wondering why I get 20. . .18. . .30 kills, when Im the only one working? What is wrong? Is there a cheat?