Hi
@johnhenry,
You could try an USB to HDMI connector or a USB dock with video output features.
I have an assembly with two monitors plus the laptop monitor and screenpad+, so 4 monitors in total.
One of the monitors connects directly to HDMi out from laptop and the other connects to an USB dock that has HDMI output...
Don't know if it'll work though, but perhaps you could get one of those docks to trial.