My new setup includes a Lenovo laptop with 2 external monitors that I use for Solidworks. When I am working, I typically have multiple models/assemblies pulled up at one time on my monitors. However, if I ever try to "Cascade" my model windows, they completely disappear off the screen while my main Solidworks window remains in place on the main monitor. The only way to bring those model screens back is if I move the main Solidworks window to my laptop monitor, then the cascade function works as normal for all model windows including ones that have disappeared. 

No, the Windows Key + arrow does not impact the model windows, only the main window. Yes, I have tried switching my main display and each monitor scaling without any results.

Is there any way to fix this issue while still utilizing all three screens?

Display 1 - External Monitor (Main Display), 2560 x 1440 @ 100% scale

Display 2 - External Monitor, 2560 x 1440 @ 100% scale

Display 3 - Laptop (typically not used for CAD), 2560 x 1600 @ 100% scale