CakePHP Join with Fields CONCAT

//AssignmentsStudentController.php

                $assistantOptions = array(
                        'joins' => array(
                                array(
                                        'table' => 'schools_students',
                                        'alias' => 'SchoolsStudent',
                                        'type' => 'INNER',
                                        'conditions' => array('Assistant.id = SchoolsStudent.student_id')
                                        )
                                ),
                        'fields' => array(
                                'Assistant.id',
                                'CONCAT(Assistant.given_name, " ", Assistant.family_name) AS Assistant__assistant_fullname'
                                ),
                        'conditions' => array(
                                'Assistant.active' => 1,
                                'Assistant.role_id' => array(4, 5, 6),
                                'SchoolsStudent.assistant' => 1,
                                'SchoolsStudent.school_id' => 1
                                ),
                        'order' => array(
                                'Assistant__assistant_fullname' => 'ASC'
                                )
                        );
                $assistants = $this->AssignmentsStudent->Assistant->find('list', $assistantOptions);

// Produces the following SQL (This works correctly in SequelPro)
SELECT `Assistant`.`id`, CONCAT(Assistant.given_name, " ", Assistant.family_name) AS Assistant__assistant_fullname FROM `jwtalks_tms`.`students` AS `Assistant` INNER JOIN `jwtalks_tms`.`schools_students` AS `SchoolsStudent` ON (`Assistant`.`id` = `SchoolsStudent`.`student_id`) WHERE `Assistant`.`active` = '1' AND `Assistant`.`role_id` IN (4, 5, 6) AND `SchoolsStudent`.`assistant` = '1' AND `SchoolsStudent`.`school_id` = 1 ORDER BY `Assistant__assistant_fullname` ASC

// Array Output is missing Assistant fullname
Array
(
    [100] =>
    [41] =>
    [39] =>
    [44] =>
    [67] =>
    [90] =>
    [76] =>
    [49] =>
    [30] =>
    [98] =>
    [102] =>
    [71] =>
    [112] =>
    [57] =>
    [116] =>
    [50] =>
    [17] =>
    [107] =>
    [52] =>
    [92] =>
    [31] =>
    [24] =>
    [18] =>
    [42] =>
    [2] =>
    [56] =>
    [38] =>
    [109] =>
    [83] =>
    [87] =>
    [75] =>
    [68] =>
    [7] =>
    [105] =>
    [85] =>
    [5] =>
    [59] =>
    [69] =>
    [22] =>
    [114] =>
)