Why doesn't the PMDG 747-400/400F have "wingviews"?

The decision to exclude the wings from the virtual cockpit model was made for performance considerations. The wingtips are barely even visible from the real plane's cockpit and the pilots need to crane their necks against the glass to even see the winglets.

It is possible to create wingviews from the external model in spot view by using a custom camera utility such as Walk and Follow.