Make sure that the rat is warm and not cold and pretty dry. I would buy some tongs and wave the rat back and forth to envoke the stalking behavior.

As far as the live aspect. I would try and talk to you dad a little more about it. Sometimes you have to do what is needed for the snake over preference. I prefer to feed my snakes outside their enclosure so that it cuts down on the possibility of aspen being digested. However, some of my snakes refuse to eat outside their enclosure so I have to give in. I would stress to your dad that he would not have to worry about the live rat being alive for very long. Its pretty quick for the most part.

The change over from live to frozen thawed sometimes doesn't happen overnight and its something that has to be a slow change than immediate. I have no doubt adventually you might get to your desired feeding habit, but maybe not at the moment. Good luck to you. :-)