×One monster has to go in per chamber, and the leftmost one has to be a Gel Baby because there's nowhere to finagle around it in there. A Wubba would block you and a Rock Golem's rubble would clog you. But the center chamber is... Confusing.

If we put a Wubba in it, we can deal with the Rock Monster in the right chamber no problem. But then we can't push the Wubba back far enough to be able to circle around it in the center chamber. (We'd, personally, err on the side of putting the Rock Golem in the right because that feels like it's intended since it's much easier to smash it than to move around the Wubba, but we may be missing something.)

Likewise, if we put a Rock Golem in it, we can move around the Wubba in the right chamber, but we can't push the rock golem far enough in the center chamber. Despite the Wubba's movement, it can be done with the right chamber; it's the blatant impossibility of the center chamber that seems to dissuade it, but also the center seems to be impossible with the Wubba in it anyways...?

Note that the right chamber can deal with both of them, but the center chamber can't.

×You should start by re-examining your assumptions about the left chamber.

×You can go with process of elimination that we were wrong about the left chamber, but we were partially about the right chamber despite griping about it. How can that be?