If I remember the situation correctly, he never asked you for a username/ password. He instructed you on how to put your username and password in a php query for the script. I know web development is not your strength, but that is what Rob is really good at! I remember this situation, because I was so surprised that you had no clue what he was talking about and you kept saying I'm not giving you my username and password when he was NEVER asking for it.
If you're talking about another situation, pardon my interruption!