Quick phone him now and tell him something has cropped up, so can't make it!
He's 'down grading' a date and testing you, he should have offered to take you out on Friday or Saturday, after his interview. If he doesn't do the 'wooing' in the first couple of dates he never will.
Unless you behave like a 'good catch', which I'm sure you are, he won't chase you. Men love to chase, it keeps them interested.
Maybe he has a girlfriend.
Once you have cancelled, wait and see what his next move is. If there isn't one, forget him.
Either way, good luck.