On the posts page, the page attributes are missing for my page contributors (where they choose the template and page parent).

I saw some other forum posts where it say to remove the ID pageparentdiv from the advanced options screen.  That worked.

HOWEVER, when I enable revisionary, it disappears again.

I need help with this quick; I have content contributors waiting to get into our new WP CMS.

Revisionary does not support revisioning of page attributes. It's more than just a UI visibility issue. The current page parent will be maintained even though it's not displayed in the revision edit form.