So as a followup, I figured out my issue to hitting "next" at that point in the wizard, and it was very simple. It appears you must also have some local device to save that image to, regardless if you are only trying to upload a image to your WDS server. This seems redundant to me, but as soon as I plugged in an external hard-drive to save that wim file to locally, the wizard let me continue. That other link for the DISM mounting/unmounting process I needed to get the Image Capture wizard to start in the first place, so I hope that also helps someone.
I'm still having some issues with the image actually uploading to my WDS server which I am still investigating. I will touch base here if I find anything else out, but I may end up just copying the locally stored wim file into my WDS server and importing that as a boot image.
Thanks,
Cliff