The script you meantion grabs a users userid from vbulletin based on their username so the userfix script is indeed working correctly. It has to if you have correctly imported your smf users into
vb. Now of course this also depends on your coppermine being correctly installed with smf because for the userfix script to grab a users userid to update your photos comments based on their username that actual username needs to exist in your vbulletin from the smf imported usernames.