How to join multiple tables in xPDO queries

$mygroups = $this->getGroupMemberships();

$criteria = $this->modx->newQuery('Contract');

$criteria->leftJoin('Client','Client');

$criteria->leftJoin('Program','Program');

$criteria->leftJoin('Location','Location', array('Program.location_id:=' => 'Location.id'));

$criteria->where(array('Contract.status_id' => 2,'OR:Contract.status_id:=' => 3));

$criteria->where(array('Client.first_name:LIKE' => "%$searchQuery%",'OR:Client.cams:LIKE' => "%$searchQuery%",'OR:Client.last_name:LIKE' => "%$searchQuery%"));

$criteria->where(array('Location.location_id:IN' => $mygroups));


$options = $this->modx->getCollectionGraph('Contract', '{ "Client": {}, "Program": { "ProgramName": {}, "Location": {}, }, }', $criteria);

$criteria->prepare();

$this->modx->log(modX::LOG_LEVEL_ERROR,'Running "getJsonPayees", sql = '.$criteria->toSQL());

SELECT (a whole lot of fields!)
FROM `flow_contract` AS `Contract` 
LEFT JOIN `flow_client` `Client` ON `Contract`.`client_id` =  `Client`.`id` 
LEFT JOIN `flow_program` `Program` ON `Contract`.`program_id` =  `Program`.`id` 
LEFT JOIN `flow_location` `Location` ON `Program`.`location_id` = 'Location.id'

WHERE  (  ( `Contract`.`status_id` = 2 OR `Contract`.`status_id` = 3 )  
AND  ( `Client`.`first_name` LIKE '%k%' OR `Client`.`cams` LIKE '%k%' OR `Client`.`last_name` LIKE '%k%' )  AND `Location`.`id` IN (1,2,3,4,5,6,7,8,9,10) )

LEFT JOIN `flow_location` `Location` ON `Program`.`location_id` = 'Location.id'

LEFT JOIN `flow_location` `Location` ON `Program`.`location_id` = `Location`.`id`

$q = 'SELECT (a whole lot of fields!)
FROM `flow_contract` AS `Contract` 
LEFT JOIN `flow_client` `Client` ON `Contract`.`client_id` =  `Client`.`id` 
LEFT JOIN `flow_program` `Program` ON `Contract`.`program_id` =  `Program`.`id` 
LEFT JOIN `flow_location` `Location` ON `Program`.`location_id` = 'Location.id'
 
WHERE  (  ( `Contract`.`status_id` = 2 OR `Contract`.`status_id` = 3 )  
AND  ( `Client`.`first_name` LIKE '%k%' OR `Client`.`cams` LIKE '%k%' OR `Client`.`last_name` LIKE '%k%' )  AND `Location`.`id` IN (1,2,3,4,5,6,7,8,9,10) )';


$query = new xPDOCriteria($modx, $q);
$query->prepare();
$query->stmt->execute();

$myrows = $query->stmt->fetchAll(PDO::FETCH_ASSOC);

$criteria->leftJoin('Location','Location', 'Program.location_id = Location.id');