Input for Fan 3 should be provided from PWMOUT3 pin of MAX31790. Correct image is shown below.
MAX31790
Production
The MAX31790 controls the speeds of up to six fans using six independent PWM outputs. The desired fan speeds (or PWM duty cycles) are written through the...
Datasheet
MAX31790 on Analog.com
Input for Fan 3 should be provided from PWMOUT3 pin of MAX31790. Correct image is shown below.