Simulate a crowd of objects flocking towards targets

I would like to generate a crowd of an object, say, a circle, and have it flow down a corridor and then flock towards multiple targets. Halfway through the simulation I’d like to move the targets. There will be walls and openings in the walls and so they need to be able to collide with the wall and enter through the gaps.

I can achieve this with one target with boids. I use a wind force to move them down a corridor, collision for the walls, and a negative force object for a target. Alternatively I can also use a goal object.

However with multiple goals I can’t seem to get the swarm to split into two. Help?