Formatted Date using Moment with AM/PM and TimeZone does not sort in FireFox

Using this code:

$.fn.dataTable.moment('YYYY-mm-dd HH:mm:ss tt zz');

To format the date and it works and sorts fine in Chrome, but the sort button does nothing in FireFox, it does display the date correctly in both. I'm assuming I need to render it somehow, but I've been unable to solve it.

                columnDefs: [
                    { 
                        targets: 6, 
                        render: [DATETIME AM/PM TIMEZONE]
                    }],