Well... I finally went ahead and rebuilt the server on which vCenter Converter Standalone was running. I then did a fresh install of the converter and reran the task and all went well. I think it might have been an issue of the wrong version *.iso being mounted as the converter helper. I had to keep manually mounting the iso to the new VM and boot before it would actually go through, and occasionally i would get prompted for "converter login" credentials.
I will chalk this up to a bad upgrade/install/accumulated junk on the vCenter system.