Local Machine

I tried to install our software program on a town hall yesterday. I had much difficulity. One of the problems was the town had a domain but the users per command of IT person told them to log onto local computer not domain log in. I told him they will not pick up domain rights as I had set up a group and permissions. He absolutely states I am wrong. I need help proving it to him. Any advice. He is not trained in IT but learning over the years how to manage their 4 servers. OOPS. Why a domain then?