I guess when you guys say "Cover Fill" you mean the Vectorial Hatching of the Surface of the element? Cover Fill is a term that applies only to a few element types (Slab, Roof, Shell, Morph, Mesh, Zone) and applies only to the Floor Plan Viewpoint. Cover Fill also applies to Fills, so yes, a Fill with the "Cover Fill" type can be placed in Elevations as well.
Is it possible that the Surface of the side of your element is overridden with another Surface that does not have Vectorial Hatching?
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