Someone please help...

I just bought a Nautilus 360 RS ARGB

My motherboard is an asus b450 mobo

My board has an AIO_PUMP header and a CPU_FAN header

Do I do as the instructions say and plug the pump into the CPU_FAN header even though I have an AIO_PUMP header?

Im noticing on the instructions on the website that I need to plug the 4 bank 3 terminal plug (essentially a 3 pin with a blank spot) into the ARGB header but I dont see it ANYWHERE

I DO see a few GEN2_1 or _2 etc headers that match the same pinouts as the plugs

My case fans are controlled by a hub that was installed when I bought the case (yes i bought a prebuilt) the hub does not have any empty bays that match the pinout of the cable.

Can I use one of these GEN2_1 or _2 etc headers for the ARGB pinout cable?

Im sorry in advance if this is a stupid question. Ive been holding off on getting an AIO for entirely too long because I dont understand this part of assembly/upgrading...