This is the exact part.

Inside the ice machine it pulls in air from near the ice making sheet, runs it across the bulb, and spits the air back out above the water distribution bar above the ice making sheet. Similar devices from other manufacturers will pull the air from all the way down in the ice bin to circulate it inside the bin as well.

As far as it being an enclosed space, ice machines are fairly sealed but are frequently opened to access the ice in the bin. They’re less sealed than your average refrigerator.