If the brute is the only character, then there is no focus.
If there is another character that the monster could get to (assuming infinite movement), then that character would be the focus and the monster would move toward it.
Wow really? I did not see it that way. I guess I need to watch for this sort of thing. I just treated #1's allies (E's) as empty spaces for the purposes of finding a focus. I see why you are correct, though.