How to fool power supply that it has DC fan installed
four wires: GND, +12V, Temp and Rotation control.

From the datasheet I deduce that instead of Temp and Rotation control there are Tacho (pulses indicating the fan's speed) and Control which probably feeds a PWM signal to the fan to control the fan's speed.

This means that this fan uses quite "standard" signals. My bet is that the supply just wants to see the "Tacho" signal so that it knows that the Fan is spinning.

I also think that you could just a standard 4-wire CPU-cooler fan (and optionally ignore the PWM Control input or use a 3 -wire fan and then not connect the PWM control signal. That 3-wire fan will then just rotate at maximum speed but will provide a Tacho signal to the supply making it operate.