Hi @garrett !
As mentioned, https://support.google.com/a/answer/2956491 there’s no option to use the hostname in #6, so what’s the purpose to change the server name?
About your last question: Yes. I edited the lines 234 and 238 to this, where nnn is the public IP:
$this->_smtpSend(“EHLO nnn.nnn.nnn.nnn”, ‘250’);