OK, I got tired of waiting on ASUS and them asking stupid questions rather than fixing their software. I have a relatively simple modification to the board that will get this working. After tracing out the circuit it's a simple matter of removing U1. Actually you could lift/cut the legs/pins 5 and 6, but removing it maybe easier. Once this is complete, the switch used to switch color/effect/mode no longer works, but I assume you don't want that functionality anyway. Actually you could repurpose this switch as a system reset switch. Just to be clear nothing else needs to be done. I've attached a picture of what the board looks like just so you can see nothing else needs to be done. No need to add wires, short anything, etc.
The software will default to 120 LEDs, so if you don't want a gap in the effect (while it's talking to LEDs from 28 - 120) make sure to set that number to 27. Presumably if you have the right connector you could use the ARGB out connector (for the fourth fan) to run an ARGB strip. Of course you'd have to add those LEDs to the total.