I found a copy of wOffice v. 2.3.3, activated it and allowed with URE to view one page for administrator and editor roles with 404 error in case of access error, exactly as on your screenshot. Then I logged-in with subscriber role and tried to view that page. I got a theme’s 404 page.
If it’s possible to get from you the latest woffice version, I’m ready to repeat this test with it. I install commercial products at my local development environment only.