How to pass Service Request Catalog User Selection value in an Approval Definition function call

I'm trying to pass the value of a user selection to an Approval Definition that uses a function call.  I've verified that the function works by hard-coding the parameter value in the script, but it passes the name of the user selection rather than the value when I try to pass it in as a parameter.

The function call in the Approval Defintion condition:

jscall("xcelSRCUNIXGroupUtils.PrivAccessCheck", "xcelSRCGenericTypeOne in $File")="yes"

returns

08/29/18 09:25:31 xcelSRCGenericTypeOne in $File
08/29/18 09:25:31 xce
08/29/18 09:25:31 no

I receive an error if I don't put the parameter in quotes.

Below is the function

function PrivAccessCheck(unixGroupName)
{
var PrivAccess="no";
smLogPrint(unixGroupName);
var unixGroupPreFix = unixGroupName.substring(0,3);
smLogPrint(unixGroupPreFix);
if ( unixGroupPreFix == "ug-" )
    {
     PrivAccess="yes";
    }
smLogPrint(PrivAccess);
return PrivAccess;
}

function smLogPrint(val)
{
 print(val);
 writeFile("../logs/sm.log","a","\n" system.functions.str(system.functions.tod()) "\t" val);
}