It should be possible to have muliple versions of Java coexist on OS X. What is the exact error message Pacifist is giving you? I've used it in the past, and it was as simple as open the application, dismiss the donate popup, and drag the package you want to look at on the Dock icon for Pacifist.
Depending on the nature of the package you downloaded from that support article (as in whether it contains all necessary Java files or just the changed), you might be able to extract that particular version of the JDK to a temporary place (like the Desktop) and copy it into the System folder (I know the JDKs used to live in /System/Library/Frameworks/JavaVM.framework/Versions. It might be slightly different now that OS X does not include Java by default and it downloads the runtime on the fly when it is first needed). One problem with this way is it might be removed in a future OSX update.