Have you done a side-by-side comparison of a "good" VRML file with the one you are getting from Creo? There are a lot of restrictions put upon student versions of Creo, to enforce what seems to be a policy of "we'll let you learn to use the software, but you can't output data that could be used for production work". There might be a formatting difference in the VRML you get from Creo that is invalid with any other programs. Similar in philosophy to the fact that you can't exchange Creo part or assembly files between the student and production versions of the software.
Just a guess on my part, but since VRML is a text-based format, you could check it out.