Have you tried setting z height to increase the bounding box size in z? Is the object rotated? Can you send me the gltf/glb file so I can try on my side?
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The issue is the origin is not centered with this model when it's rotated, I will look at adding an ACE which creates a centered bbox, shifting the origin and the size at the same time. This may also need to be a property for it to do the same in the editor. Right now I have to do this to center it: