Dynamic Roles - not evaluating

I'm not sure what I'm doing wrong here.  The function that I use to get users, returns a comma delimted string.

The roles in 9.2 take a list.  I've tried to pass the comma delimited string - doesn't work.  Not on todo list.  Can't see actions. 

I've tried to convert the string into a list a return a list instead of a string. This doesn't work.

edit: I'm using this to convert.

List.Convert(mystring) -  myString would be a comma delimited string

I've been able to see the results of my role function when passing it to a form memo field as a test.

I've also updated euser and eassignment so that all users are lower case.

Any ideas?