Kill Stealing in TD

[FireEffect]

Whats the best way to prevent kill stealing in a TD. In the right position, a 500 range tower and kill steal from 3 different people. It is a 8 player survival, so i can have 4 creep teams I was thinking of making 1 person able to kill only 1 creep team to prevent kill stealing, an example would be Zoator TD Survival. The arrangement is like this :

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Where should I place the different creep teams? I mightve not explained this well, but i cant figure out how to say it.

EDIT - Doh, found out where to place them. it was simpler than what i was making of it.