I am retrieving usernames into a multivalue text variable but I can't get them to display properly

I am retrieving usernames into a multivalue text variable in an existing 6.6 app to be shown on a portal report but I can't get them to display properly.
Some of the rows on the report are from older versions of the pm but the set up of the variables is same, the only difference is that the older versions were populated from a DB using a lowercase function which has been removed for the new ones.
When the report column is set to the user name format I can see the older rows formatted as a name eg Adam Smith, but new rows don't show at all.
If I switch to User or Group Name or the group profile format I see values for all rows but they are shown as the user name and not formatted eg smitha.
I'm not sure why the older data is being treated differently as the code seems to be the same.
Is there any way to convert the pv to display all rows with formatted names?
I have tried various functions but I'm obviously missing the correct combination and if an...

OriginalPostID-121436