Help with overrides - Oxidized integration

My company hasn’t standardized on a username and passwords. We have around 8 combinations in use. I’m trying to map the IP address (which is also the hostname) to a group to use in the oxidized configuration. I’m just trying to get one to come back with the correct mapping when I query the API. I tried these combination so far for the one host.
$config[‘oxidized’][‘maps’][‘group’][‘hostname’][] = array(‘regex’ => ‘/^172.16.1.1/’, ‘group’ => ‘tacacs-internal’);
$config[‘oxidized’][‘maps’][‘group’][‘hostname’][] = array(‘regex’ => ‘/172.16.1.1/’, ‘group’ => ‘tacacs-internal’);
$config[‘oxidized’][‘maps’][‘group’][‘hostname’][] = array(‘regex’ => ‘172.16.1.1’, ‘group’ => ‘tacacs-internal’);
$config[‘oxidized’][‘maps’][‘group’][‘hostname’][] = array(‘match’ => ‘172.16.1.1’, ‘group’ => ‘tacacs-internal’);

I am still seeing the device in the default group.
oxidized@librenms:/home/oxidized$ curl -H ‘X-Auth-Token: xxxx’ http://localhost/api/v0/oxidized

{
    "hostname": "172.16.16.1",
    "os": "ios",
    "ip": "",
    "group": "default"
},

Thanks in advance

Found my typo!!!

can you share the correct format for the override used in the same situation right now.