When we use a Callout to apply a Saved View within our composition model, that promoted view is missing certain resymbolized drawing graphics. This was working before so something has changed. I've discovered that if I copy the referenced 3D geometry directly into the composition model then those same graphics display as expected, but of course I cannot do that in production.
The issue in this case was that the Cut Plane and Forward/Reflected View levels as defined within the applicable Parts (different than the Definition/3D Model levels) were turned off in the reference file attachment. So even if the Callout were to be applied directly in the referenced DGN file itself, those resymbolized graphics would not display. This also explains why the resymbolized graphics did display when the geometry was copied directly into the composition model, since these same Cut Plane and Forward/Reflected View part levels were not turned off there.