How can I lock rotation about two axis'?

I have a sandcastle.

Lets say the blue line represents the y-axis, the green line the x-axis, and the red line the z-axis. I don’t know if that is accurate or not…if not, please correct me.

I only want to permit rotation around the y-axis.

How can I do this?

To lock all three, I can do:

viewer.scene.screenSpaceCameraController.enableRotate = false;

but, I don’t see a way to lock only two.

I thought there might be some way to use:

but, that only allows locking of a single axis, if I am interpreting the documentation and behavior correctly.