my best advice is to change their fan, there are plenty of silent fan, like arctic f12 pwm, you should look at 120mm fan at least, they move more air, maybe you can fit some 140mm
like i did it here(this is a g-balde that was using a 90, and i put in a 120mm
did this already. I have 2 silverstone fhp-141's (140mm fan with 120mm mounting holes) in a push/pull config. cant get my miners below 60c in my second bedroom with AC blasting.
it's because we are in summer, my tests were done in autumn, it make sense, then you need to find another solution, like basement, cellar, don't know if your garage will cut it, otherwise you can add plenty of big fan, like 480mm fan or around that
but if your TAMB is already too high, you can't do much with fan only, you need something that refrigerate