I think the best way to implement a real SL is to tell the EA to close a long position if the current price = the highest high value over the current and pervious bars minus your stop amount. And then have your fake SL further away and just modify as normal. That way the broker can't know where your real stop is. I notice that sometimes in live trading the broker can send some abnormal prices which makes an ea modify the stop then gets stopped out.
Crazy!