by Ken Task.
Welcome.
For others that might follow ... from what I've read, when one uses 'localhost' in the config.php file MySQL uses socket connect which is different than if one used the IP address for localhost (127.0.0.1).
The issue was a busted socket ... which is worth investigating further. Suggest pursuing that for your server flavor with some true experts in MacOSX server.
'spirit of sharing', Ken