Thank you.
In the mean time I figured out a work around. For anyone interested I set monitor 2 and 3 “duplicate” and connected to the remote machine with two monitors. Then to ease switching back and forth I used the open source program “MonitorProfileSwitcher” to quickly switch back and forth between a 1-2-3 configuration to a 1-23 config.
This is not nearly as great as a feature built in to NoMachine but it works.