Wow, that's the worst guide I've ever seen. Force Quit all open applications? Then right-clicking instead of dragging the icons off the Dock? I think they're just trying to make it look like the Mac is as difficult as possible.
I have a "Remove Office" tool in the "Additional Tools" folder inside the Microsoft Office 2011 folder. That should do the trick, although it will definitely completely uninstall and require a reinstall. I believe there is some way to deauthorize it without that, but someone else would have to provide that solution.