I'm not sure of what you mean...

The only EA broker can kill are scalpers because they can widden the spread so much scalper become useless.

The other thing broker can do is stop loss hunting but brokers who do that go out of the market sooner or later.

To prevent stop loss hunting, you just need to implement a hidden real SL and a fake larger SL in your EA (to prevent catastrophic event) and that's about it.