Another question is, what are the outputs of the two, 2-pin, PWM ports on the aquaero 6 for? Are they for PWM control only?

The
manual states:
4.4. Connector “PWM 1/2”
Pulse width modulated 12 V outputs, maximum current load 1 A, carrier frequency 15 kHz.
Pin assignment: Pin 1: VCC
Pin 2: GND
Is that the same signal the fans send out if they are set to PWM?
And are the aquaero controller Data source 'Power output 1' & 'Power output 2' the way to control those two PWM ports?
Could I drive a Swiftech 8 way spiltter with one PWM port using a
2-pin cable, as long as power is also provided to the splitter?