200 mm outtake fan not working proper anymore .. Do I really need it?

Ok it is clear that my 200 mm outtake fan is no longer working properly. Now with the way this pc is put together it has the PSU shooting the hot air both out the back and blowing it upward into the case. Also there is a 120 mm fan pulling air out the back of the case. In regards to the cpu and gpu they are air cooled. The case all this is going on in is the Antec 1100. Do I really need this 200 mm fan as the outtake up top or can I slap a 120 mm fan or multiple 120 mm fans on the sides (2 on the windowed side and 1 behind the motherboard) and be fine. Thanks for taking the time to read this and thanks for any help you can provide.

Oh and someone would just say simply replace the 200 mm fan and be done with it and well I can get the fan for $24.99 plus tax with free shipping but I thought maybe just putting 120 mm fans on the side might be cheaper. The 200 mm fan btw is proprietary so no using just another one with the case so I can’t find one cheaper.