The key is to start round 2 later in the day. I started about 8 hours after round 2 began so there were no bots in my bracket and I won easily with 2.8 mil. But that doesn't matter when you get to round 3 and all the bots are there.
Don't listen to the people saying it's possible to legitimately get 200k+ points per hour. They will never explain how it's possible other than saying some people are better. Thats a lie. I'm a professional gamer and I've tried every way possible to reach that level. It's not possible without manipulating the API code.