Undefined error when getting location qty

The issue I am having is I am consistently getting the following error when executing a user event script in NetSuite:

TypeError: Cannot read property "amazon" from undefined

The code I can share is as follows:

var qtyAvail = 0;
qtyAvail = rec.getValue('locationquantityavailable');
if(!qtyAvail || qtyAvail === 'undefined' || qtyAvail === null || isNaN(qtyAvail) || typeof qtyAvail === "undefined"){
                qtyAvail = 0;

            }  
  location = rec.getValue(kColumns[3]);
            if(location == 7 ||location == 16 ||location == 20 ||location == 3 ||location == 19 ||location == 1 ||location == 27 ||location == 27){   
                if(location == 7){
                    fba = qtyAvail;
                    if(!fba){
                        qtyAvail = 0;
                    }                   
                }
...more business code here....
return {

            amazon: fba,
            ups: upsName
}
I am calling the return values like:

var itemQty = getLocationQty(item);
           if(itemQty.amazon){
               var fbaStock = itemQty.amazon;