Update:
The miner came. So, you have to sand off (or in my case slice off with a sharp knife) the little protective stubs that make sure that the fan goes in the right way, since the one on the antminer is twice as wide, and the fans HAVE to be 4-pin PWM or it won't recognize them at all. Once you have them plugged in and screwed on (and be careful when screwing on, the stock screws are super long, and when you put on the slimmer fan, they actually go deep enough do damage the mainboard, so get some shorter screws or use washers), the fans do eventually spin up, the RPM is recognized, but.. the shitty part is that the machine is hard coded to only work with 6000RPM fans, so it does work for 5-10 seconds, then stops, and logs the error 'Fan Err! Disable PIC! Fan1 speed is too low, 1510rpm at 50PWM', since I guess it's looking for 3000 at 50%
And so I put the stock fans back on and manually set the fan speed to its minimum, and guess what, the temperature sits at around 55 degrees at 1710rpm, with the same (or even worse) airflow as Noctua at similar RPMs, but way louder. So this sucks. Even though the fans are fully capable, due to this stupid exception you can't use properly sound engineered fans
The next step would be for me I guess to try a pwm emulator on an Arduino. Stay tuned.