Pulling first name from LMS

I am struggling with using JavaScript to capture the user's first and last names from the LMS (Vector Solutions). They store the user name as "Firstname, Lastname, Middle". This is the code I am using but it is not working. I was able to insert the date using JavaScript.

var lmsAPI = parent;
var name = lmsAPI.GetStudentName();
var nameArray = name.split(",");
var lastName = nameArray[1];
var firstName = nameArray[0];
var player = GetPlayer();
player.SetVar('first_name',firstName);
player.SetVar('last_name',lastName);