Using window aircon unit inside

I have a 2HP Panasonic window type aircon. The front half of the aircon is facing the lounge area which is to be cooled and then the back half vents the hot exhaust into a small laundry room. The laundry room has a large open window area (just anti-insect netting).

Unfortunately the laundry room fills up with hot air in a few minutes and the aircon pretty much stops putting out any cold air.

This video shows my different attempts at making this unit work for me. I start by creating a kind of exhaust system that I hoped would take the hot air away from the aircon and out the window. Although the hot air was flowing out of the flexible duct very strongly, It didn't really seem to be doing enough and the metal exhaust system i'd made was getting extremely hot.

My second attempt is to use an extractor fan to suck cool air in from outside and feed it into the aircons intake. This seems to work much better. The laundry room still gets extremely hot and most of the hot air stays in the room rather than escaping out of the window. But as long as the cool air is being sucked in from outside and pushed into the aircons intake, it seems to continue pushing out cool air. Although the longer it runs and the more hot air that builds up in the room, the less effective it seems to be.