How to freeze rotation and movement on child Object?

In my game I imported a model which I nested under an empty object to get the correct orientation axis for perform rotations and movements in scripts. The problem is that while I froze the position on the Z axis and rotation on the X and Y axis for the parent object, when I actually move the empty game Object (and consequently the model), if I hit something the empty game object will remain without rotation but the (nested) model will start spinning on axis I don't want it to. To freeze rotation on the model, it requires a Rigidbody component but if I give it one, then, when I move the empty game object the model stands still.

How can I approach this issue?

Ps: I'm moving the object by adding forces to its rigid body!