The four batteries are monitored and controlled by the BMS and have a VE Can data cable network to do the monitoring. The BMS acts as an energy monitor and displays the results on the screen of the Color Control GX. The Quattro or MultiPlus is used for shore or generator charging and as an inverter. The solar charge controller is also linked to the network to control charging of the batteries. This diagram shows two alternative ways of connecting the alternators, in one it is using a Buck Boost DC DC Converter as the interface between the alternator and the battery. This offers the most control, can limit the draw on the alternator and modify the voltage to match the requirements of the batteries. The other way is a simpler combiner which links the start and house batteries and which is controlled by the BMS.
At the time of writing (February 2018) Victron does not stock the HE Lithium batteries in the US. They are available but delivery time is around two months. The other batteries that work in this scenario are being discontinued but there are still lots left and they have had a price drop making them more appealing.