I've received an email from the developer of the Rawkee plugin with this very useful information on how to properly export a Maya Binary to an X3D.
Under File, click the box next to "Export All".
1) Make sure the "Consolidate Files Locally" box is checked. - If this is
not checked, the exporter will use the path on your machine in the URL
field of the ImageTexture node. This option was put in because one of the
groups helping me debug the software wanted this.
2) Make sure the "Overwrite Existing Texture and Audio Files" is checked.